Journal articles: 'Photonic Devices Operating'

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Lin, Shawn-Yu, J. G. Fleming, and E. Chow. "Two- and Three-Dimensional Photonic Crystals Built with VLSI Tools." MRS Bulletin 26, no. 8 (August 2001): 627–31. http://dx.doi.org/10.1557/mrs2001.157.

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The drive toward miniature photonic devices has been hindered by our inability to tightly control and manipulate light. Moreover, photonics technologies are typically not based on silicon and, until recently, only indirectly benefited from the rapid advances being made in silicon processing technology. In the first part of this article, the successful fabrication of three-dimensional (3D) photonic crystals using silicon processing will be discussed. This advance has been made possible through the use of integrated-circuit (IC) fabrication technologies (e.g., very largescale integration, VLSI) and may enable the penetration of Si processing into photonics. In the second part, we describe the creation of 2D photonic-crystal slabs operating at the λ = 1.55 μm communications wavelength. This class of 2D photonic crystals is particularly promising for planar on-chip guiding, trapping, and switching of light.

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Ivanov, Alexander, Oleg Morozov, Airat Sakhabutdinov, Artem Kuznetsov, and Ilnur Nureev. "Photonic-Assisted Receivers for Instantaneous Microwave Frequency Measurement Based on Discriminators of Resonance Type." Photonics 9, no. 10 (October 11, 2022): 754. http://dx.doi.org/10.3390/photonics9100754.

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Photonic-assisted receivers for instantaneous microwave frequency measurement are devices used to measure the instantaneous frequency and amplitude of one or more microwave signals in the optical range, typically used in radar systems. Increasingly higher demands are placed on frequency range, accuracy and resolution during the development of instantaneous microwave frequency measurement applications, and these demands can be satisfied by the creation of new devices and operating principles. To permit further development in this area, it is necessary to generalize the experience gained during the development of devices based on frequency and amplitude discriminators of resonance type, including advanced ones with the best performances. Thus, in this report, we provide an overview of all the basic types of approaches used for the realization of photonic-assisted receivers based on fiber Bragg gratings, integrated Fano and optical ring resonators, Brillouin gain spectrum, and so on. The principles of their operation, as well as their associated advantages, disadvantages, and existing solutions to identified problems, are examined in detail. The presented approaches could be of value and interest to those working in the field of microwave photonics and radar systems, as we propose an original method for choosing photonic-assisted receivers appropriate for the characterization of multiple frequency measurements.

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HARRIS, JAMES S. "(GaIn)(NAsSb): MBE GROWTH, HETEROSTRUCTURE AND NANOPHOTONIC DEVICES." International Journal of Nanoscience 06, no. 03n04 (June 2007): 269–74. http://dx.doi.org/10.1142/s0219581x07004699.

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Dilute nitride GaInNAs and GaInNAsSb alloys grown on GaAs have quickly become excellent candidates for a variety of lower cost 1.2–1.6 μm lasers, optical amplifiers, and high power Raman pump lasers that will be required in the networks to provide high speed communications to the desktop. Because these quantum well active regions can be grown on GaAs , the distributed mirror technology for vertical cavity surface emitting lasers coupling into waveguides and fibers and photonic crystal structures can be readily combined with GaInNAsSb active regions to produce a variety of advanced photonic devices that will be crucial for advanced photonic integrated circuits. GaInNAs ( Sb ) provides several new challenges compared to earlier III–V alloys because of the limited solubility of N , phase segregation, nonradiative defects caused by the low growth temperature, and ion damage from the N plasma source. This paper describes progress in overcoming some of the material challenges and progress in realizing record setting edge emitting lasers, the first VCSELs operating at 1.5 μm based on GaInNAsSb and integrated photonic crystal and nanoaperture lasers.

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Panyaev, Ivan S., Dmitry G. Sannikov, Nataliya N. Dadoenkova, and Yuliya S. Dadoenkova. "Three-periodic 1D photonic crystals for designing the photonic optical devices operating in the infrared regime." Applied Optics 60, no. 7 (February 25, 2021): 1943. http://dx.doi.org/10.1364/ao.415966.

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Davis, Timothy J., Daniel E. Gómez, and Ann Roberts. "Plasmonic circuits for manipulating optical information." Nanophotonics 6, no. 3 (October 26, 2016): 543–59. http://dx.doi.org/10.1515/nanoph-2016-0131.

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AbstractSurface plasmons excited by light in metal structures provide a means for manipulating optical energy at the nanoscale. Plasmons are associated with the collective oscillations of conduction electrons in metals and play a role intermediate between photonics and electronics. As such, plasmonic devices have been created that mimic photonic waveguides as well as electrical circuits operating at optical frequencies. We review the plasmon technologies and circuits proposed, modeled, and demonstrated over the past decade that have potential applications in optical computing and optical information processing.

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Ferrier, L., P. Rojo-Romeo, E. Drouard, X. Letatre, and P. Viktorovitch. "Slow Bloch mode confinement in 2D photonic crystals for surface operating devices." Optics Express 16, no. 5 (2008): 3136. http://dx.doi.org/10.1364/oe.16.003136.

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Damulira, Edrine, Muhammad Nur Salihin Yusoff, Ahmad Fairuz Omar, and Nur Hartini Mohd Taib. "A Review: Photonic Devices Used for Dosimetry in Medical Radiation." Sensors 19, no. 10 (May 14, 2019): 2226. http://dx.doi.org/10.3390/s19102226.

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Numerous instruments such as ionization chambers, hand-held and pocket dosimeters of various types, film badges, thermoluminescent dosimeters (TLDs) and optically stimulated luminescence dosimeters (OSLDs) are used to measure and monitor radiation in medical applications. Of recent, photonic devices have also been adopted. This article evaluates recent research and advancements in the applications of photonic devices in medical radiation detection primarily focusing on four types; photodiodes – including light-emitting diodes (LEDs), phototransistors—including metal oxide semiconductor field effect transistors (MOSFETs), photovoltaic sensors/solar cells, and charge coupled devices/charge metal oxide semiconductors (CCD/CMOS) cameras. A comprehensive analysis of the operating principles and recent technologies of these devices is performed. Further, critical evaluation and comparison of their benefits and limitations as dosimeters is done based on the available studies. Common factors barring photonic devices from being used as radiation detectors are also discussed; with suggestions on possible solutions to overcome these barriers. Finally, the potentials of these devices and the challenges of realizing their applications as quintessential dosimeters are highlighted for future research and improvements.

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Kim, Gyungock, Jeong Woo Park, In Gyoo Kim, Sanghoon Kim, Sanggi Kim, Jong Moo Lee, Gun Sik Park, et al. "Low-voltage high-performance silicon photonic devices and photonic integrated circuits operating up to 30 Gb/s." Optics Express 19, no. 27 (December 16, 2011): 26936. http://dx.doi.org/10.1364/oe.19.026936.

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Rashed, Ahmed Nabih Zaki. "High Performance Photonic Devices for Multiplexing/Demultiplexing Applications in Multi Band Operating Regions." Journal of Computational and Theoretical Nanoscience 9, no. 4 (April 1, 2012): 522–31. http://dx.doi.org/10.1166/jctn.2012.2055.

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Al-Tameemi, Saif, and Mohammed Nadhim Abbas. "All-Optical Universal Logic Gates at Nano-scale Dimensions." Iraqi Journal of Nanotechnology, no. 2 (December 7, 2021): 34–43. http://dx.doi.org/10.47758/ijn.vi2.49.

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Though photonics displays an attractive solution to the speed limitation of electronics, decreasing the size of photonic devices is one of the major problems with implementing photonic integrated circuits that are regarded the challenges to produce all-optical computers. Plasmonic can solve these problems, it be a potential solution to fill the gaps in the electronics (large bandwidth and ultra-high speed) and photonics (diffraction limit due to miniaturization size). In this paper, Nano-rings Insulator-Metal-Insulator (IMI) plasmonic waveguides has been used to propose, design, simulate, and perform all-optical universal logic gates (NOR and NAND gates). By using Finite Element Method (FEM), the structure of the proposed plasmonic universal logic gates are designed and numerically simulated by two dimensions (2-D) structure. Silver and Glass materials were chosen to construct proposed structure. The function of the proposed plasmonic NOR and NAND logic gates was achieved by destructive and constructive interferences principle. The performance of the proposed device is measured by three criteria; the transmission, extension ratio, and modulation depth. Numerical simulations show that a transmission threshold (0.3) which allows achieving the proposed plasmonic universal logic gates in one structure at 1550 nm operating wavelength. The properties of this devise was as follows: The transmission exceeds 100% in one state of NAND gate, medium values of Extension Ratio, very high MD values, and very small foot print. In the future, this device will be the access to the nanophotonic integrated circuits and it has regarded fundamental building blocks for all-optical computers.

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Leuermann, Jonas, Adrián Fernández-Gavela, Antonia Torres-Cubillo, Sergio Postigo, Alejandro Sánchez-Postigo, Laura M. Lechuga, Robert Halir, and Íñigo Molina-Fernández. "Optimizing the Limit of Detection of Waveguide-Based Interferometric Biosensor Devices." Sensors 19, no. 17 (August 23, 2019): 3671. http://dx.doi.org/10.3390/s19173671.

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Waveguide-based photonic sensors provide a unique combination of high sensitivity, compact size and label-free, multiplexed operation. Interferometric configurations furthermore enable a simple, fixed-wavelength read-out making them particularly suitable for low-cost diagnostic and monitoring devices. Their limit of detection, i.e., the lowest analyte concentration that can be reliably observed, mainly depends on the sensors response to small refractive index changes, and the noise in the read-out system. While enhancements in the sensors response have been extensively studied, noise optimization has received much less attention. Here we show that order-of-magnitude enhancements in the limit of detection can be achieved through systematic noise reduction, and demonstrate a limit of detection of ∼ 10 - 8 RIU with a silicon nitride sensor operating at telecom wavelengths.

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IGA, KENICHI. "SURFACE EMITTING LASERS." International Journal of High Speed Electronics and Systems 03, no. 03n04 (September 1992): 263–77. http://dx.doi.org/10.1142/s0129156492000102.

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In this paper we review the progress and basic technology of vertical cavity surface emitting lasers together with related parallel surface operating optical devices. First, the concept of a vertical cavity surface emitting laser is presented, and then currently developed devices and their performances will be introduced. We will then feature some technical issues, such as multilayer structures, 2-dimensional arrays, photonic integration, etc. Lastly, future prospects for parallel lightwave subsystems using surface emitting lasers will be discussed.

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Larger, Laurent. "Complexity in electro-optic delay dynamics: modelling, design and applications." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1999 (September 28, 2013): 20120464. http://dx.doi.org/10.1098/rsta.2012.0464.

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Nonlinear delay dynamics have found during the last 30 years a particularly prolific exploration area in the field of photonic systems. Besides the popular external cavity laser diode set-ups, we focus in this article on another experimental realization involving electro-optic (EO) feedback loops, with delay. This approach has strongly evolved with the important technological progress made on broadband photonic and optoelectronic devices dedicated to high-speed optical telecommunications. The complex dynamical systems performed by nonlinear delayed EO feedback loop architectures were designed and explored within a huge range of operating parameters. Thanks to the availability of high-performance photonic devices, these EO delay dynamics led also to many successful, efficient and diverse applications, beyond the many fundamental questions raised from the observation of experimental behaviours. Their chaotic motion allowed for a physical layer encryption method to secure optical data, with a demonstrated capability to operate at the typical speed of modern optical telecommunications. Microwave limit cycles generated in similar EO delay oscillators showed significantly improved spectral purity thanks to the use of a very long fibre delay line. Last but not least, a novel brain inspired computational principle has been recently implemented physically in photonics for the first time, again on the basis of an EO delay dynamical system. In this latter emerging application, the computed result is obtained by a proper ‘read-out’ of the complex nonlinear transients emerging from a fixed point, the transient being issued by the injection of the information signal to be processed.

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Krraoui, Houssemeddine, Charlotte Tripon-Canseliet, Ivan Maksimovic, Stefan Varault, Gregoire Pillet, Stefano Maci, and Jean Chazelas. "Characterization of Optically-Reconfigurable Metasurfaces by a Free Space Microwave Bistatic Technique." Applied Sciences 10, no. 12 (June 25, 2020): 4353. http://dx.doi.org/10.3390/app10124353.

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Microwave performance extraction of optically-controlled squared frequency-selective surface (FSS) structures printed on highly resistive (HR) silicon substrate are presented, from a innovative bistatic microwave photonic characterization technique operating in the 40 to 60 GHz frequency range, commonly used for radar cross section (RCS) measurements. According to typical physical photon absorption phenomenon occurring in photoconductive materials, these structures demonstrate experimentally a bandpass filtering frequency response cancellation through reflection coefficient measurements, under specific incident collective illumination in the Near-infrared region (NIR). This behaviour is attributed to their microwave surface impedance modification accordingly to the incident optical power, allowing ultrafast reconfigurability of such devices by optics

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Overvig, Adam C., Sajan Shrestha, and Nanfang Yu. "Dimerized high contrast gratings." Nanophotonics 7, no. 6 (June 27, 2018): 1157–68. http://dx.doi.org/10.1515/nanoph-2017-0127.

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AbstractMetasurfaces and planar photonic crystals are two classes of subwavelength diffractive optical devices offering novel functionalities. The former employ independently operating subwavelength “meta-units” as their building blocks, while the latter exploit the collective response of many periodic building blocks. High contrast gratings (HCGs) are an example of one-dimensional (1D) planar photonic crystals with large refractive index contrast, exhibiting large in-plane scattering even with a limited number of grating periods. They are best known for their broadband features. Low contrast gratings (LCGs) are known for their control over sharp spectral features but require many periods due to small in-plane scattering. We explore a class of symmetry-broken HCGs called dimerized high contrast gratings (DHCGs), which have a period-doubling perturbation applied. DHCGs support modes accessible by free-space illumination with a long, controllable photon lifetime (inversely proportional to the magnitude of the perturbation) and reduced lateral energy divergence (confined by the high index contrast of the grating). We catalogue and clarify the resonant modes introduced by the dimerizing perturbation in 1D DHCGs and briefly explore the increased in-plane scattering present in two-dimensional (2D) DHCGs. We introduce an approach maximizing lateral localization by band structure engineering in the unperturbed HCG and using the dimerizing perturbation to generate sharp spectral features in devices with small footprint. We confirm the simultaneous control of photon lifetime and lateral localization with full-wave simulations of finite-sized DHCGs. We conclude by numerically demonstrating two compact devices (an optical modulator and a refractive index sensor) benefitting from the unique design freedoms of DHCGs.

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Rahman, I. K. M. Reaz, Shiekh Zia Uddin, Hyungjin Kim, Naoki Higashitarumizu, and Ali Javey. "Low voltage AC electroluminescence in silicon MOS capacitors." Applied Physics Letters 121, no. 19 (November 7, 2022): 193502. http://dx.doi.org/10.1063/5.0120507.

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Low power silicon based light source and detector are attractive for on-chip photonic circuits given their ease of process integration. However, conventional silicon light emitting diodes emit photons with energies near the band edge where the corresponding silicon photodetectors lack responsivity. On the other hand, previously reported hot carrier electroluminescent silicon devices utilizing a reverse biased diode require high operating voltages. Here, we investigate hot carrier electroluminescence in silicon metal–oxide–semiconductor capacitors operating under transient voltage conditions. During each voltage transient, large energy band bending is created at the edge of the source contact, much larger than what is achievable at a steady state. As a result, electrons and holes are injected efficiently from a single source contact into the silicon channel at the corresponding voltage transient, where they subsequently undergo impact ionization and phonon-assisted interband recombination. Notably, we show low voltage operation down to 2.8 V by using a 20 nm thick high-[Formula: see text] gate dielectric. We show further voltage scaling is possible by reducing the gate dielectric thickness, thus presenting a low voltage platform for silicon optoelectronic integrated circuits.

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Liao, Wenyuan, Rui Gao, Yuebo Liu, Jide Zhang, Shuwang Li, Hao Niu, Shaohua Yang, and Canxiong Lai. "Degradation Characteristics and Reliability Assessment of 1310 nm VCSEL for Microwave Photonic Link." Applied Sciences 12, no. 11 (May 30, 2022): 5532. http://dx.doi.org/10.3390/app12115532.

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The long-term reliability of the commercially available vertical-cavity surface-emitting laser (VCSEL) at 1310 nm wavelength is investigated. To do so, a high current accelerated life test is used to evaluate the 1310 nm VCSEL reliability. Variations of properties that depend on the operating condition are characterized by the light-current-voltage, leakage current and low-frequency noise. When the aging current is 6 mA, 8 mA and 10 mA, the maximum output power reduces by 5%, 6% and 15% of the initial value, respectively. It is demonstrated theoretically and experimentally that the leakage current increases and reverse bias breakdown voltage decreases after the accelerated current aging test. The current noise power spectral density increases after the device ages, and the noise increases with the augment of the electrical stress. When the bias current of VCSEL is below the threshold, the frequency index factor and noise amplitude gradually increase with the bias current increase. Further, lifetime fitting curves of the devices at an accelerating current of 6 mA, 8 mA and 10 mA are obtained, and the median lifetime of 67 years at the operating current is extrapolated.

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Pandey, Girijesh Narayan, Narendra Kumar, Pawan Singh, K. B. Thapa, Sonika, and Vanshika Singhania. "Tunable Reflection Properties and Photonic Bandgap Behavior of a One-Dimensional Metamaterial-Superconductor-Based Ternary Photonic Crystal." IOP Conference Series: Materials Science and Engineering 1263, no. 1 (October 1, 2022): 012002. http://dx.doi.org/10.1088/1757-899x/1263/1/012002.

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In the present communication, we have investigated the tunable reflection properties and photonic bandgap variation of a one-dimensional metamaterial and superconductor based ternary photonic crystal. To design the 1D ternary photonic crystal, we have taken three alternate layers of metamaterial, superconductor (BSSCO), and silica (SiO2). Transfer matrix method (TMM) is employed to determine the optical reflection properties of the considered 1DPC for TE-mode by varying five parameters, viz. incident angle, superconductor temperature, thickness and refractive index of dielectric layer, and number of unit cells. It is noted that the ternary PC exhibits the features of tunable narrow band reflector, whose width increases with increase in the incident angle with a blue shift, and decreases with operating temperature of superconductor with red shift. It also enhances with increase in the dielectric layer thickness in low frequency region, and decreases in high frequency regime with red shifts. We obtain only one PBG at n3=1.46 in low frequency regime, while with increase in the refractive index multiple gaps are obtained in different frequency regions having distinct widths at n3=2.4 and 3.4. An increase in the number of unit cells causes increase in the reflectance, wherein no PBG is found below N=8. This analysis gives some insights to design tunable devices based on narrowband reflectivity in the terahertz frequency regime, including THz-metadevices, emitters, thermo-optical devices, and security sensors.

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Lourenço, J., Q. R. Al-Taai, A. Al-Khalidi, E. Wasige, and J. Figueiredo. "Resonant Tunnelling Diode – Photodetectors for spiking neural networks." Journal of Physics: Conference Series 2407, no. 1 (December 1, 2022): 012047. http://dx.doi.org/10.1088/1742-6596/2407/1/012047.

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Abstract Spike-based neuromorphic devices promise to alleviate the energy greed of the artificial intelligence hardware by using spiking neural networks (SNNs), which employ neuron like units to process information through the timing of the spikes. These neuron-like devices only consume energy when active. Recent works have shown that resonant tunnelling diodes (RTDs) incorporating optoelectronic functionalities such as photodetection and light emission can play a major role on photonic SNNs. RTDs are devices that display an N-shaped current-voltage characteristics capable of providing negative differential conductance (NDC) over a range of the operating voltages. Specifically, RTD photodetectors (RTD-PDs) show promise due to their unique mixture of the structural simplicity while simultaneously providing highly complex non-linear behavior. The goal of this work is to present a systematic study of the how the thickness of the RTD-PD light absorption layers (100, 250, 500 nm) and the device size impacts on the performance of InGaAs RTD-PDs, namely on its responsivity and time response when operating in the third (1550 nm) optical transmission window. Our focus is on the overall characterization of the device optoelectronic response including the impact of the light absorption on the device static current-voltage characteristic, the responsivity and the photodetection time response. For the static characterization, the devices I-V curves were measured under dark conditions and under illumination, giving insights on the light induced I-V tunability effect. The RTD-PD responsivity was compared to the response of a commercial photodetector. The characterization of the temporal response included its capacity to generate optical induced neuronal-like electrical spike, that is, when working as an opto-to-electrical spike converter. The experimental data obtained at each characterization phase is being used for the evaluation and refinement of a behavioral model for RTD-PD devices under construction.

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Zhao, Yixiong, Kunj Himanshu Vora, Gerd vom Bögel, Karsten Seidl, and Jens Weidenmüller. "Design and simulation of a photonic crystal resonator as a biosensor for point-of-care applications." tm - Technisches Messen 87, no. 7-8 (July 26, 2020): 470–76. http://dx.doi.org/10.1515/teme-2019-0127.

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AbstractPoint-of-care (POC) devices are essential for rapid testing of samples for early diagnosis of diseases. The accuracy and the sensitivity of the POC device depend mainly on the biosensors. The currently used POC devices require specialized operating personnel, long sample preparation time and high equipment costs. We aim to explain a bio-sensing concept using a photonic crystal (PC) resonator that would mitigate the drawbacks of the present sensing techniques. Photonic crystals consist of spatially arranged dielectric materials presenting a band gap that prevents electromagnetic waves of certain frequency range to propagate through it. PC resonators have shown to have very high sensitivities for bio-sensing applications at THz frequencies. A PC resonator with a high Q-factor is designed and simulated to detect the changes in the surrounding dielectric permittivity. As an application for detecting specific biomolecules, a protocol for surface functionalization has been explained. This will enable the selective binding of biomolecules from the sample. Shift in resonant frequency and attenuation in magnitude at the peak resonant frequency can be observed from the simulation results. These changes in the resonator properties can be indicative of the presence of a particular biomolecule or pathogen and its concentration within the sample.

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Qasim, Mehdi, Jinan B. Al-Dabbagh, Ahmed N. Abdalla, M. M. Yusoff, and Gurumurthy Hegde. "Radial Basis Function Neural Network Model for Optimizing Thermal Annealing Process Operating Condition." Nano Hybrids 4 (May 2013): 21–31. http://dx.doi.org/10.4028/www.scientific.net/nh.4.21.

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Optimum thermal annealing process operating condition for nanostructured porous silicon (nPSi) by using radial basis function neural network (RBFNN) was proposed. The nanostructured porous silicon (nPSi) layer samples prepared by electrochemical etching process (EC) of p-type silicon wafers under different operatingconditions, such as varyingetchingtime (Et), annealing temperature (AT), and annealing time (At). The electrical properties of nPSi show an enhancement with thermal treatment.Simulation result shows that the proposed model can be used in the experimental results in this operating condition with acceptable small error. This model can be used in nanotechnology based photonic devices and gas sensors.

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Chen, Yong-Qiang, Guang-Yuan Xu, Jun Wang, Yu Fang, Xing-Zhi Wu, Ya-Qiong Ding, and Yong Sun. "Electromagnetic diode based on asymmetric microwave photonic crystal." Acta Physica Sinica 71, no. 3 (2022): 034701. http://dx.doi.org/10.7498/aps.71.20211291.

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A subwavelength electromagnetic diode scheme in a microwave waveguide system is proposed by using an asymmetric photonic crystal (PC) cavity side-coupled with electromagnetically induced transparency like (EIT-like) metamaterials. It is found that the composite PC-EIT configuration can generate tenfold <i>Q</i>-factor enlargement, accompanied with enhanced nonreciprocal electromagnetic localization simultaneously. Further study of the measured one-way response exhibits excellent electromagnetic diode performance including 19.7 dB transmission contrast and 7 dBm operating power at a working frequency of 1.329 GHz. We emphasize that such high-contrast transmission and low-threshold diode actions are not at costs of greatly increasing volume and drastically reducing transmission. Our findings may benefit the design of compact nonreciprocal devices in the integrated optical nanocircuits.

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Jin, Xinxin, Guohua Hu, Meng Zhang, Tom Albrow-Owen, Zheng Zheng, and Tawfique Hasan. "Environmentally stable black phosphorus saturable absorber for ultrafast laser." Nanophotonics 9, no. 8 (January 28, 2020): 2445–49. http://dx.doi.org/10.1515/nanoph-2019-0524.

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AbstractBlack phosphorus (BP) attracts huge interest in photonic and optoelectronic applications ranging from passive switch for ultrafast lasers to photodetectors. However, the instability of chemically unfunctionalized BP in ambient environment due to oxygen and moisture remains a critical barrier to its potential applications. Here, the parylene-C layer was used to protect inkjet-printed BP-saturable absorbers (BP-SA), and the efficacy of this passivation layer was demonstrated on the stable and continuous operation of inkjet-printed BP-SA in harsh environmental conditions. BP-SA was integrated in an erbium-doped ring laser cavity and immersed in water at ~60°C during operation for investigation. Mode-locked pulses at ~1567.3 nm with ~538 fs pulse width remained stable for >200 h. The standard deviation of spectral width, central wavelength, and pulse width were 0.0248 nm, 0.0387 nm, and 2.3 fs, respectively, in this period, underscoring the extreme stability of BP-SA against high temperature and humidity. This approach could enable the exploitation of BP-based devices for photonic applications when operating under adverse environmental conditions.

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Liu, Ruiyan, Leon Shterengas, Aaron Stein, Gela Kipshidze, Dmitri Zakharov, Kim Kisslinger, and Gregory L. Belenky. "Photonic Crystal Surface Emitting Diode Lasers with λ near 2 µm." Photonics 9, no. 12 (November 22, 2022): 891. http://dx.doi.org/10.3390/photonics9120891.

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Epitaxially regrown electrically pumped photonic crystal surface emitting lasers (PCSELs) operating near 2 µm were designed and fabricated within a III-V-Sb material system. A high-index-contrast photonic crystal layer was incorporated into the laser heterostructures by air-pocket-retaining epitaxial regrowth. Transmission electron microscopy studies confirmed uniform and continuous AlGaAsSb initial growth over the nano-patterned GaSb surface, followed by the development of the air-pockets. The PCSEL threshold current density had a minimal value of ~170 A/cm2 in the 160–180 K temperature range when the QW gain spectrum aligned with the Γ2 band edge of the photonic crystal. The devices operated in a continuous wave regime at 160 K. The divergence and polarization of the multimode laser beam emitted from the 200 µm × 200 µm PCSEL aperture were controlled by filamentation.

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Pérez-Armenta, Carlos, Alejandro Ortega-Moñux, José Manuel Luque-González, Robert Halir, Pedro Reyes-Iglesias, Jens H. Schmid, Pavel Cheben, íñigo Molina-Fernández, and J. Gonzalo Wangüemert Pérez. "Polarization independent 2×2 multimode interference coupler with bricked subwavelength metamaterial." EPJ Web of Conferences 266 (2022): 01009. http://dx.doi.org/10.1051/epjconf/202226601009.

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The silicon-on-insulator (SOI) platform enables high integration density in photonic integrated circuits while maintaining compatibility with CMOS fabrication processes. Nevertheless, its inherently high modal birefringence hinders the development of polarization-insensitive devices. The dispersion and anisotropy engineering leveraging subwavelength grating (SWG) metamaterials makes possible the development of polarization agnostic waveguide components. In this work we build upon the bricked SWG metamaterial nanostructures to design a polarization independent 2×2 multimode interference (MMI) coupler for the 220 nm SOI platform, operating in the telecom O-band. The designed device exhibits a 160 nm bandwidth with excess loss, polarization dependent loss and imbalance below 1 dB and phase error lower than 5°.

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Förster, Christian, Volker Cimalla, M. Stubenrauch, Carsten Rockstuhl, Klemens Brueckner, Matthias A. Hein, Jörg Pezoldt, and Oliver Ambacher. "Micromachining of Novel SiC on Si Structures for Device and Sensor Applications." Materials Science Forum 527-529 (October 2006): 1111–14. http://dx.doi.org/10.4028/www.scientific.net/msf.527-529.1111.

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In this paper the multifariousness of SiC/Si heterostructures for device and sensor applications will be demonstrated. 3C-SiC based microelectromechanical resonator beams (MEMS) with different geometries actuated by the magnetomotive effect operating under ambient conditions were fabricated. The resonant frequency reaches values up to 2 MHz. The applications of these resonators are the measurement of the viscosity of liquids or mass detection. Furthermore, photonic devices in the form of SiC/Si infrared gratings for wavelength and polarization filters in infrared spectra are processed. SiC wear protection for a dosing system with the possibility to dose nano- or picoliter droplets of water based liquids as well as SiC nanomasking for catalytic agent nanostructures are demonstrated.

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Torres-Company, Víctor, Gladys Mínguez-Vega, Vicent Climent, Jesús Lands, and Pedro Andrés. "New photonic devices for ultrafast pulse processing operating on the basis of the diffraction-dispersion analogy." Journal of Physics: Conference Series 139 (November 1, 2008): 012013. http://dx.doi.org/10.1088/1742-6596/139/1/012013.

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Zhang, Aojie, Zihao Wang, Hao Ouyang, Wenhao Lyu, Jingxuan Sun, Yuan Cheng, and Bo Fu. "Recent Progress of Two-Dimensional Materials for Ultrafast Photonics." Nanomaterials 11, no. 7 (July 8, 2021): 1778. http://dx.doi.org/10.3390/nano11071778.

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Owing to their extraordinary physical and chemical properties, two-dimensional (2D) materials have aroused extensive attention and have been widely used in photonic and optoelectronic devices, catalytic reactions, and biomedicine. In particular, 2D materials possess a unique bandgap structure and nonlinear optical properties, which can be used as saturable absorbers in ultrafast lasers. Here, we mainly review the top-down and bottom-up methods for preparing 2D materials, such as graphene, topological insulators, transition metal dichalcogenides, black phosphorus, and MXenes. Then, we focus on the ultrafast applications of 2D materials at the typical operating wavelengths of 1, 1.5, 2, and 3 μm. The key parameters and output performance of ultrafast pulsed lasers based on 2D materials are discussed. Furthermore, an outlook regarding the fabrication methods and the development of 2D materials in ultrafast photonics is also presented.

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Jainth, Sandhya. "Design and simulation of strip loaded and rib waveguide with integration of 2D material." Indian Journal of Science and Technology 13, no. 40 (October 31, 2020): 4262–74. http://dx.doi.org/10.17485/ijst/v13i40.1648.

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Objective- To design Graphene-Silicon based rib waveguide and reduce the losses in the strip in order to meet the requirement for ultra-fast & ultrahigh optical bandwidth communication and computing in integrated optical devices. Method –Propagation losses and effective refractive index are the two key parameters. In order to meet the objective, the effects of Graphene for manufacturing passive devices/components in the field of Integrated Photonic like integrated optical waveguide have been analysed by measuring the changes in propagation losses and effective refractive index of the silicon photonics devices for operating at different wavelengths. Findings- We have presented the design and simulation of SOI (Silicon-on-Insulator) platforms with 2D layer materials (graphene) which has been used along with their mode of propagation, effective refractive index (ne f f ), propagation losses (dB/cm) and varying wavelength range for optimum performance. In addition to this, we have also calculated the boundary limit for both the speed and bandwidth. We also reported the development of Silicon rib waveguide, Graphene-Silicon based rib waveguide and Ge on SOI with graphene later at the top of strip waveguide.Minimum loss of strip waveguide is 2.9 dB/cm which has been obtained for Mid-IR wavelength generally used for high power mid- IR sensing.

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Spitz, Olivier, and Frédéric Grillot. "A review of recent results of mid-infrared quantum cascade photonic devices operating under external optical control." Journal of Physics: Photonics 4, no. 2 (March 7, 2022): 022001. http://dx.doi.org/10.1088/2515-7647/ac5494.

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Abstract The purpose of this article is to gather recent findings about the non-linear dynamics of distributed feedback quantum cascade lasers (QCLs), with a view on practical applications in a near future. As opposed to other semiconductor lasers, usually emitting in the visible or the near-infrared region, QCL technology takes advantage of intersubband transitions and quantum engineering to emit in the mid-infrared and far-infrared domain. This peculiarity and its physical consequences were long considered as a detrimental characteristic to generate non-linear dynamics under external optical control. However, we show that a wide diversity of phenomena, from high-dimensional chaos to giant pulses can be observed when the QCL is under external optical feedback or under optical injection and with a continuous current bias. Most of these phenomena have already been observed in other semiconductor lasers under optical feedback or under optical injection, which allows us to compare QCLs with their interband counterparts.

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Zeng, Min, Flavia Artizzu, Jing Liu, Shalini Singh, Federico Locardi, Dimitrije Mara, Zeger Hens, and Rik Van Deun. "Boosting the Er3+ 1.5 μm Luminescence in CsPbCl3 Perovskite Nanocrystals for Photonic Devices Operating at Telecommunication Wavelengths." ACS Applied Nano Materials 3, no. 5 (April 10, 2020): 4699–707. http://dx.doi.org/10.1021/acsanm.0c00701.

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Passian, Ali, and Neena Imam. "Nanosystems, Edge Computing, and the Next Generation Computing Systems." Sensors 19, no. 18 (September 19, 2019): 4048. http://dx.doi.org/10.3390/s19184048.

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It is widely recognized that nanoscience and nanotechnology and their subfields, such as nanophotonics, nanoelectronics, and nanomechanics, have had a tremendous impact on recent advances in sensing, imaging, and communication, with notable developments, including novel transistors and processor architectures. For example, in addition to being supremely fast, optical and photonic components and devices are capable of operating across multiple orders of magnitude length, power, and spectral scales, encompassing the range from macroscopic device sizes and kW energies to atomic domains and single-photon energies. The extreme versatility of the associated electromagnetic phenomena and applications, both classical and quantum, are therefore highly appealing to the rapidly evolving computing and communication realms, where innovations in both hardware and software are necessary to meet the growing speed and memory requirements. Development of all-optical components, photonic chips, interconnects, and processors will bring the speed of light, photon coherence properties, field confinement and enhancement, information-carrying capacity, and the broad spectrum of light into the high-performance computing, the internet of things, and industries related to cloud, fog, and recently edge computing. Conversely, owing to their extraordinary properties, 0D, 1D, and 2D materials are being explored as a physical basis for the next generation of logic components and processors. Carbon nanotubes, for example, have been recently used to create a new processor beyond proof of principle. These developments, in conjunction with neuromorphic and quantum computing, are envisioned to maintain the growth of computing power beyond the projected plateau for silicon technology. We survey the qualitative figures of merit of technologies of current interest for the next generation computing with an emphasis on edge computing.

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Yu, C. H., X. Y. Chen, X. D. Luo, W. W. Xu, and P. S. Liu. "Analysis of Low Dimensional Nanoscaled Inversion-Mode InGaAs MOSFETs for Next-Generation Electrical and Photonic Applications." Advances in Condensed Matter Physics 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/423791.

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The electrical characteristics of In0.53Ga0.47As MOSFET grown with Si interface passivation layer (IPL) and highkgate oxide HfO2layer have been investigated in detail. The influences of Si IPL thickness, gate oxide HfO2thickness, the doping depth, and concentration of source and drain layer on output and transfer characteristics of the MOSFET at fixed gate or drain voltages have been individually simulated and analyzed. The determination of the above parameters is suggested based on their effect on maximum drain current, leakage current, saturated voltage, and so forth. It is found that the channel length decreases with the increase of the maximum drain current and leakage current simultaneously. Short channel effects start to appear when the channel length is less than 0.9 μm and experience sudden sharp increases which make device performance degrade and reach their operating limits when the channel length is further lessened down to 0.5 μm. The results demonstrate the usefulness of short channel simulations for designs and optimization of next-generation electrical and photonic devices.

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Zhang, Yiyue, Masoumeh Keshavarz, Elke Debroye, Eduard Fron, Miriam Candelaria Rodríguez González, Denys Naumenko, Heinz Amenitsch, et al. "Two-dimensional perovskites with alternating cations in the interlayer space for stable light-emitting diodes." Nanophotonics 10, no. 8 (June 1, 2020): 2145–56. http://dx.doi.org/10.1515/nanoph-2021-0037.

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Abstract Lead halide perovskites have attracted tremendous attention in photovoltaics due to their impressive optoelectronic properties. However, the poor stability of perovskite-based devices remains a bottleneck for further commercial development. Two-dimensional perovskites have great potential in optoelectronic devices, as they are much more stable than their three-dimensional counterparts and rapidly catching up in performance. Herein, we demonstrate high-quality two-dimensional novel perovskite thin films with alternating cations in the interlayer space. This innovative perovskite provides highly stable semiconductor thin films for efficient near-infrared light-emitting diodes (LEDs). Highly efficient LEDs with tunable emission wavelengths from 680 to 770 nm along with excellent operational stability are demonstrated by varying the thickness of the interlayer spacer cation. Furthermore, the best-performing device exhibits an external quantum efficiency of 3.4% at a high current density (J) of 249 mA/cm2 and remains above 2.5% for a J up to 720 mA cm−2, leading to a high radiance of 77.5 W/Sr m2 when driven at 6 V. The same device also shows impressive operational stability, retaining almost 80% of its initial performance after operating at 20 mA/cm2 for 350 min. This work provides fundamental evidence that this novel alternating interlayer cation 2D perovskite can be a promising and stable photonic emitter.

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Li, Siqing, Changjian Lv, Hongyu Luo, Linghao Cui, Zhixu Jia, Jianfeng Li, Weiping Qin, and Guanshi Qin. "Ultrathin gold nanowires as broadband saturable absorbers for ultrashort pulsed lasers." Laser Physics Letters 19, no. 9 (August 10, 2022): 095102. http://dx.doi.org/10.1088/1612-202x/ac8679.

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Abstract Ultrathin gold nanowires (UGNWs) with a diameter of ⩽2 nm have attracted much attention because of their high aspect ratios, unusual physical properties and potential applications in nanoelectronics, sensors and photonics. Despite recent advances on UGNWs and the related devices, nonlinear optical properties of UGNWs and their application on photonic devices (e.g. ultrashort pulsed lasers) remain largely unexplored. Here we show that UGNWs can be used as broadband saturable absorbers (SAs) for constructing ultrashort pulsed lasers with an operating wavelength range from near-infrared to mid-infrared (MIR). UGNWs are prepared by using a silane-mediated approach, and then mixed with polyvinyl alcohol to form the UGNWs film. The UGNWs film not only show strong absorption from visible to MIR spectral region (over 25 μm), but also possess the nonlinear saturable absorption properties in the spectral region. As the UGNWs film SA is inserted into an erbium or thulium doped silica fiber laser cavity, stable passively mode-locked lasers at 1562.2 or 1970 nm with a pulse width of a few hundreds of femtoseconds is obtained, respectively. Especially, by inserting the UGNWs film SA into a holmium/praseodymium codoped fluoride fiber laser cavity, stable passively mode-locked laser at 2864 nm is achieved. Our results show that the UGNWs film are promising SAs for constructing broadband ultrashort pulsed lasers.

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Kanwal, Saima, Jing Wen, Binbin Yu, Xu Chen, Dileep Kumar, Yi Kang, Chunyan Bai, Saima Ubaid, and Dawei Zhang. "Polarization Insensitive, Broadband, Near Diffraction-Limited Metalens in Ultraviolet Region." Nanomaterials 10, no. 8 (July 23, 2020): 1439. http://dx.doi.org/10.3390/nano10081439.

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Metasurfaces in the ultraviolet spectrum have stirred up prevalent research interest due to the increasing demand for ultra-compact and wearable UV optical systems. The limitations of conventional plasmonic metasurfaces operating in transmission mode can be overcome by using a suitable dielectric material. A metalens holds promising wavefront engineering for various applications. Metalenses have developed a breakthrough technology in the advancement of integrated and miniaturized optical devices. However, metalenses utilizing the Pancharatnam–Berry (PB) phase or resonance tuning methodology are restricted to polarization dependence and for various applications, polarization-insensitive metalenses are highly desirable. We propose the design of a high-efficiency dielectric polarization-insensitive UV metalens utilizing cylindrical nanopillars with strong focusing ability, providing full phase delay in a broadband range of Ultraviolet light (270–380 nm). The designed metalens comprises Silicon nitride cylindrical nanopillars with spatially varying radii and offers outstanding polarization-insensitive operation in the broadband UV spectrum. It will significantly promote and boost the integration and miniaturization of the UV photonic devices by overcoming the use of Plasmonics structures that are vulnerable to the absorption and ohmic losses of the metals. The focusing efficiency of the designed metalens is as high as 40%.

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Hänsel, Andreas, and Martijn Heck. "Feasibility of Telecom-Wavelength Photonic Integrated Circuits for Gas Sensors." Sensors 18, no. 9 (August 31, 2018): 2870. http://dx.doi.org/10.3390/s18092870.

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To be of commercial interest, gas sensors must optimise, among others, sensitivity, selectivity, longevity, cost and measurement speed. Using the example of ammonia, we establish that integrated optical sensors provide means to maintain the benefits of optical detection set-ups at, in principle, a lower cost and smaller footprint than currently available commercial products. Photonic integrated circuits (PICs) can be used in environmental and agricultural monitoring. The small footprint and great cost scaling of PICs allow for sensor networks with multiple devices. We show, that Indium Phosphide based commercial foundries reached the technological maturity to enable ammonia detection levels at less than 100 ppb. The current unavailability of portable, low cost ammonia sensors with such detection levels prevents emission monitoring, for example, in pig farms. The feasibility of these sensors is investigated by applying the common noise figures of the multiproject wafer platforms operating around 1550 nm to a model for an absorption measurement. The analysis is extended to other relevant gas species with absorption features near telecom-wavelengths.

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Encomendero, Jimy, Vladimir Protasenko, Debdeep Jena, and Huili Grace Xing. "Influence of collector doping setback in the quantum transport characteristics of GaN/AlN resonant tunneling diodes." Applied Physics Express 14, no. 12 (November 12, 2021): 122003. http://dx.doi.org/10.35848/1882-0786/ac345e.

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Abstract Harnessing resonant tunneling transport in III-nitride semiconductors to boost the operating frequencies of electronic and photonic devices, requires a thorough understanding of the mechanisms that limit coherent tunneling injection. Towards this goal, we present a concerted experimental and theoretical study that elucidates the impact of the collector doping setback on the quantum transport characteristics of GaN/AlN resonant tunneling diodes (RTDs). Employing our analytical model for polar RTDs, we quantify the width of the resonant-tunneling line shape, demonstrating that the setback helps preserve coherent injection. This design results in consistently higher peak-to-valley-current ratios (PVCRs), obtaining a maximum PVCR = 2.01 at cryogenic temperatures.

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Montoya Cardona, Jorge Andres, Nelson Dario Gomez Cardona, Esteban Gonzalez Valencia, Pedro Torres Trujillo, and Erick Reyes Vera. "Tunable Mode Converter Device Based on Photonic Crystal Fiber with a Thermo-Responsive Liquid Crystal Core." Photonics 7, no. 1 (December 19, 2019): 3. http://dx.doi.org/10.3390/photonics7010003.

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A compact tunable mode converter device based on the thermo-optically characteristics of liquid crystals (LCs) is proposed and numerically analyzed herein. The proposed mode converter consists of an asymmetric dual-core photonic crystal fiber (PCF) with a highly thermo-responsive LC core. The verification of the proposed mode converter was ensured through an accurate PCF analysis based on the vector finite element method. With an appropriate choice of the design parameters associated with the LC core, phase matching at a single wavelength is available in the important O-band wavelength region. The simulation results showed that high conversion efficiencies between LP01 and LP11 mode are readily achieved over a broad wavelength range from 1278 nm to 1317 nm. Likewise, the tunable capability of the proposed mode converter was evaluated when it was submitted to thermal changes; thus, we evidence the strong thermo-responsive dependence of the operating wavelength, mode conversion efficiency and full-width at the half maximum (FWHM) bandwidth. Finally, the fabrication tolerances of the devices were also investigated. Therefore, the thermo-responsive characteristics of this novel PCF mode converter can be of fundamental importance in the future space division multiplexing technology.

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Kempa, Thomas J., and Charles M. Lieber. "Semiconductor nanowire solar cells: synthetic advances and tunable properties." Pure and Applied Chemistry 86, no. 1 (January 22, 2014): 13–26. http://dx.doi.org/10.1515/pac-2014-5010.

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Abstract The solar power received by Earth far exceeds global power demands. Despite this, infrastructure shortages and high capital costs prevent the wide-scale adoption of photovoltaics to displace conventional energy technologies relying on carbon-based fuels. In response, new concepts and materials have been explored to develop next-generation solar cells capable of operating more efficiently and cheaply. Over the past decade, single semiconductor nanowire (NW) and NW array devices have emerged as promising platforms with which to examine new concepts. Small distances in NWs allow for efficient charge separation while tunable photonic modes permit light absorption properties distinct from bulk materials. Furthermore, the synthesis and fabrication of NW devices presents new opportunities such as with incorporation of complex heterostructures or use of cheaper substrates. Here, we present a critical discussion of the benefits and remaining challenges related to utilization of NWs for solar energy conversion and emphasize the synthetic advances leading towards significant improvement in the electrical and optical performance of NW devices. We conclude by articulating the unique capabilities of solar cells assembled from multiple, distinct NWs.

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Goyal, Amit Kumar, and Yehia Massoud. "Interface Edge Mode Confinement in Dielectric-Based Quasi-Periodic Photonic Crystal Structure." Photonics 9, no. 10 (September 21, 2022): 676. http://dx.doi.org/10.3390/photonics9100676.

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In this paper, the localization of optical interface edge-states is analyzed for a dielectric material-based quasi-periodic photonic crystal (QPhC) structure. The design comprises a bilayer PhC structure, where layers are arranged in a Fibonacci configuration to introduce quasi-periodicity. The impact of local symmetric sub-structures on Eigenstate coupling is considered over a wider wavelength range. This confirms the localization of interface edge modes for different wavelengths at the structural local resonators, where the number of local resonators depends on the length of the QPhC. The proposed seven-element QPhC structure shows a strong Tamm-like top interface edge mode localization for a 45.04° incident angle at 750 nm operating wavelength, whereas a bulk interface guided mode is also excited for a higher incident angle of around 79°. The investigation facilitates the development of reconfigurable devices to excite both bulk interface and surface interface edge modes with improved field intensities for spectroscopy and sensing applications.

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Ma, Xiao, and Hoi Wai Choi. "Observation of ground loop signals in GaN monolithically integrated devices." Journal of Vacuum Science & Technology B 41, no. 1 (January 2023): 012207. http://dx.doi.org/10.1116/6.0002245.

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The observation of ground loop signals in nonelectrically isolated GaN monolithic systems has prompted an investigation on its origins. The study is carried out with devices comprising monolithic light-emitting diodes (LED) and photodetectors (PD) that are either electrically isolated by completely etching through the GaN epitaxial layers, or nonelectrically isolated devices where the etch terminates at the n-GaN layer, through TCAD simulations and experiments. While the devices behave identically to DC input signals, a signal can be observed across the PD of the nonelectrically isolated devices when an AC signal is fed to the LED, even at voltages below the LED’s turn-on voltage. The [Formula: see text] phase difference of the output PD potential with respect to the input LED potential indicates that the signal, regarded as a ground loop signal, couples through the junction capacitance of the LED and PD. The ground loop signal increases with increasing frequency due to the frequency-dependence of the junction impedance. The insertion of a grounded metal line between the LED and PD reduces the ground loop signal, but not to a sufficient extent not to affect the photovoltage. The findings illustrate the necessity of electrical isolation among devices for GaN monolithic systems, especially those operating at higher frequencies, such as photonic integrated systems.

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Bang, Nguyen Huy, Dinh Xuan Khoa, Nguyen Le Thuy An, Vu Ngoc Sau, Doan Hoai Son, and Le Van Doai. "Influence of Doppler broadening on cross-Kerr nonlinearity in a four-level inverted-Y system: An analytical approach." Journal of Nonlinear Optical Physics & Materials 28, no. 03 (September 2019): 1950031. http://dx.doi.org/10.1142/s0218863519500310.

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In this work, we study the influence of Doppler broadening on cross-Kerr nonlinearity in a four-level inverted-Y atomic system under electromagnetically induced transparency (EIT) condition. The first- and third-susceptibilities in the presence of Doppler effect are derived as a function of probe, signal and coupling beams and temperature of medium. Under EIT condition, cross-Kerr nonlinearity is enhanced several orders of magnitude compared to that without EIT. The Doppler effect leads to a reduction in the transparent efficiency and thus reduces the amplitude of cross-Kerr nonlinear coefficient. For hot atomic gaseous medium, such consideration of the Doppler effect may be useful for experimental observations and apply to photonic devices operating at different temperature conditions.

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Notomi, Masaya, Takasumi Tanabe, Akihiko Shinya, Eiichi Kuramochi, and Hideaki Taniyama. "On-Chip All-Optical Switching and Memory by Silicon Photonic Crystal Nanocavities." Advances in Optical Technologies 2008 (June 22, 2008): 1–10. http://dx.doi.org/10.1155/2008/568936.

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We review our recent studies on all-optical switching and memory operations based on thermo-optic and carrier-plasma nonlinearities both induced by two-photon absorption in silicon photonic crystal nanocavities. Owing to high-Q and small volume of these photonic crystal cavities, we have demonstrated that the switching power can be largely reduced. In addition, we demonstrate that the switching time is also reduced in nanocavity devices because of their short diffusion time. These features are important for all-optical nonlinear processing in silicon photonics technologies, since silicon is not an efficient optical nonlinear material. We discuss the effect of the carrier diffusion process in our devices, and demonstrate improvement in terms of the response speed by employing ion-implantation process. Finally, we show that coupled bistable devices lead to all-optical logic, such as flip-flop operation. These results indicate that a nanocavity-based photonic crystal platform on a silicon chip may be a promising candidate for future on-chip all-optical information processing in a largely integrated fashion.

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Kuwabara, Mitsuki, Susumu Noda, and Yasushi Takahashi. "Ultrahigh-Q Photonic Nanocavity Devices on a Dual Thickness SOI Substrate Operating at Both 1.31- and 1.55-µm Telecommunication Wavelength Bands." Laser & Photonics Reviews 13, no. 2 (January 3, 2019): 1800258. http://dx.doi.org/10.1002/lpor.201800258.

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Rymanov, V., M. Palandöken, S. Dülme, T. Tekin, and A. Stöhr. "Compact Photonic Package for High-Power E-Band (60–90 GHz) Photoreceiver Modules." International Symposium on Microelectronics 2013, no. 1 (January 1, 2013): 000883–86. http://dx.doi.org/10.4071/isom-2013-thp43.

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In this work, we present a novel photonic package for high-power photoreceiver modules operating within the E-band (60–90 GHz). The developed Kovar package features a compact size of only 6×3.5×2 cm3 and comprises an optical single-mode fiber (SMF) input, DC bias supply connections and a WR-12 output for coupling out of the radio frequency (RF) signal. As integration platform, a RF laminate submount with implemented planar bias-T based upon grounded coplanar waveguide (GCPW) transmission line circuitry is used for efficient mmW propagation, concluding in a GCPW-to-WR-12-transition. Finite element method (FEM) simulations have been carried out to analyze the frequency range of interest. Besides applied adhesive and wire bonding approaches for assembly inside the package, the RF submount exhibits sections for hybrid integration of single components, e.g. of a high-frequency waveguide photodiode. Optionally, up to two high-electron-mobility-transistor (HEMT) power amplifiers can be integrated within the GCPW circuitry. In addition, the RF laminate is mounted on a brass platform. For uniform thermal expansion within the module, a Peltier element is integrated. Concerning the saturation output power of given HEMT amplifiers, e.g. in the order of +17.5 dBm, corresponding power levels are achievable for packaged devices. For instance, an output RF power of only −19.5 dBm within the 71–76 GHz band is required from the photodiode in conjunction with two cascaded HEMT amplifiers, which results in a total gain of ~37 dB. A small series of the introduced device has been already fabricated. First experimental achievements with in-house fabricated modules will be presented.

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Azzam, Shaimaa I., and Alexander V. Kildishev. "Time-domain dynamics of reverse saturable absorbers with application to plasmon-enhanced optical limiters." Nanophotonics 8, no. 1 (November 23, 2018): 145–51. http://dx.doi.org/10.1515/nanoph-2018-0139.

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AbstractAn advanced full-wave time-domain numerical model for reverse saturable absorption (RSA) is presented and verified. Rate equations describing atomic relaxations and excitation dynamics are coupled to the Maxwell equations by using a Lorentzian oscillator, which models the kinetics-dependent light–matter interactions. The presented novel technique provides a versatile multiphysics framework for designing complex structures and integrating diverse material models that were not previously possible. The multiphysics framework allows capturing the behavior of the RSA materials embedded in artificial photonic nanostructures that cannot be analyzed with established techniques such as the Beer–Lambert law. To showcase the importance of the full-wave RSA analysis coupled to carrier kinetics, we analyze two plasmon-enhanced optical limiters: a metal grating and a Fabry–Perot cavity-like structure where we decrease the unenhanced limiter threshold by a factor of 3 and 13, respectively. This is a promising approach for developing RSA devices operating at reduced illumination levels and thereby significantly expanding their area of applicability to areas such as protective eyewear and automatically dimmed windows. By exploring the dynamic behavior of a given RSA system, this framework will provide critical insights into the design of transformative photonic devices and their complementary optical characterization, and serve as an invaluable utility for guiding the development of synthetic absorbing materials. We believe that our multiphysics models are crucial enabling tools that lay a necessary foundation for the numerical machinery required for the realization and optimization of optical limiting and all-optical switching systems.

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Vovk, Ilia A., Vladimir V. Lobanov, Aleksandr P. Litvin, Mikhail Yu Leonov, Anatoly V. Fedorov, and Ivan D. Rukhlenko. "Band Structure and Intersubband Transitions of Three-Layer Semiconductor Nanoplatelets." Nanomaterials 10, no. 5 (May 12, 2020): 933. http://dx.doi.org/10.3390/nano10050933.

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This paper presents the first general theory of electronic band structure and intersubband transitions in three-layer semiconductor nanoplatelets. We find a dispersion relation and wave functions of the confined electrons and use them to analyze the band structure of core/shell nanoplatelets with equal thicknesses of the shell layers. It is shown that the energies of electrons localized inside the shell layers can be degenerate for certain electron wave vectors and certain core and shell thicknesses. We also show that the energies of intersubband transitions can be nonmonotonic functions of the core and shell thicknesses, exhibiting pronounced local minima and maxima which can be observed in the infrared absorption spectra. Our results will prove useful for the design of photonic devices based on multilayered semiconductor nanoplatelets operating at infrared frequencies.

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Kanwal, Saima, Jing Wen, Binbin Yu, Dileep Kumar, Xu Chen, Yi Kang, Chunyan Bai, and Dawei Zhang. "High-Efficiency, Broadband, Near Diffraction-Limited, Dielectric Metalens in Ultraviolet Spectrum." Nanomaterials 10, no. 3 (March 9, 2020): 490. http://dx.doi.org/10.3390/nano10030490.

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Ultraviolet (UV) optical devices have plenteous applications in the fields of nanofabrication, military, medical, sterilization, and others. Traditional optical components utilize gradual phase accumulation phenomena to alter the wave-front of the light, making them bulky, expensive, and inefficient. A dielectric metasurface could provide an auspicious approach to precisely control the amplitude, phase, and polarization of the incident light by abrupt, discrete phase changing with high efficiency due to low absorption losses. Metalenses, being one of the most attainable applications of metasurfaces, can extremely reduce the size and complexity of the optical systems. We present the design of a high-efficiency transmissive UV metalens operating in a broadband range of UV light (250–400 nm) with outstanding focusing characteristics. The polarization conversion efficiency of the nano-rod unit and the focusing efficiency of the metasurface are optimized to be as high as 96% and 77%, respectively. The off-axis focusing characteristics at different incident angles are also investigated. The designed metalens that is composed of silicon nitride nanorods will significantly uphold the advancement of UV photonic devices and can provide opportunities for the miniaturization and integration of the UV nanophotonics and its applications.

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Montereali, R. M., F. Bonfigli, E. Nichelatti, V. Nigro, M. Piccinini, and M. A. Vincenti. "Visible radiophotoluminescence of colour centres in lithium fluoride: from lasers to versatile radiation sensors." Journal of Physics: Conference Series 2298, no. 1 (August 1, 2022): 012001. http://dx.doi.org/10.1088/1742-6596/2298/1/012001.

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Abstract The peculiar photoluminescence characteristics of radiation-induced colour centres in lithium fluoride (LiF), well known for applications in optically-pumped tuneable lasers and broad-band miniaturised light-emitting photonic devices operating at room-temperature, are under exploitation in passive imaging detectors and dosimeters based on visible radiophotoluminescence in LiF crystals and polycrystalline thin films. Their high intrinsic spatial resolution, wide dynamic range and large field of view, combined with easy handling, ambient-light operation and no development need, allow to successfully extend their use from X-ray imaging to proton-beam advanced diagnostics and dosimetry, even at those low dose values that are typical of hadrontherapy. After exposure, the latent images stored in LiF as local formations of F2 and F3 + aggregate defects are read with an optical fluorescence microscope under illumination in the blue spectral range. Their visible emission intensity was found to be linearly proportional to the dose over at least three orders of magnitude, so that bi-dimensional LiF solid-state dosimeters based on spectrally-integrated radiophotoluminescence reading can be envisaged. Taking advantage of the low thickness of LiF thin films, transversal proton beam dose mapping was demonstrated at low proton energies, even at high doses. Recent results and advances concerning LiF crystals and polycrystalline thin film characterisation in the linearity range are presented and discussed with the aim of highlighting challenges related to increasing the LiF film detector radiation sensitivity to both particles (protons) and photons (X-rays), although therapeutic dose values typical of clinical radiotherapy are still a big challenge.

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Journal articles on the topic 'Photonic Devices Operating'

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