Journal articles: 'Transverse magneto focusing'

1

Bykova, D. V., A. E. Afanasiev, and V. I. Balykin. "Sharp Focusing of an Atomic Beam with the Doppler and Sub-Doppler Laser Cooling Mechanisms in a Two-Dimensional Magneto-Optical Trap." JETP Letters 118, no. 1 (July 2023): 14–20. http://dx.doi.org/10.1134/s0021364023601549.

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The focusing of an atomic beam with the use of a two-dimensional magneto-optical trap in order to increase the number of atoms in the region of their laser cooling and localization near an atom chip is discussed. Two regimes of the interaction of atoms with a focusing laser field are considered: (i) the Doppler interaction regime, which occurs at small detunings of the laser field from the atomic resonance, and (ii) the sub-Doppler interaction regime, which occurs at large detunings of the laser field from the atomic resonance. The efficiency of focusing in the first case is low because of the momentum diffusion. It has been shown that the momentum diffusion in the sub-Doppler cooling mechanism is insignificant and, as a result, the broadening of the transverse velocity distribution of atoms is small. The sharp focusing of the atomic beam is possible in this interaction regime.

2

SUMMERS, D. J., S. B. BRACKER, L. M. CREMALDI, R. GODANG, D. B. CLINE, A. A. GARREN, G. G. HANSON, et al. "6D IONIZATION MUON COOLING WITH TABLETOP RINGS." International Journal of Modern Physics A 20, no. 16 (June 30, 2005): 3851–56. http://dx.doi.org/10.1142/s0217751x05027795.

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Progress on six dimensional ionization muon cooling with relatively small rings of magnets is described. Lattices being explored include scaling sector cyclotrons with edge focusing and strong focusing, fixed field alternating gradient (FFAG) rings. Ionization cooling is provided by high pressure hydrogen gas which removes both transverse and longitudinal momentum. Lost longitudinal momentum is replaced using radio frequency (RF) cavities, giving a net transverse emittance reduction. The longer path length in the hydrogen of higher momentum muons decreases longitudinal emittance at the expense of transverse emittance. Thus emittance exchange allows these rings to cool in all six dimensions and not just transversely. Alternatively, if the RF is located after the ring, it may be possible to cool the muons by stopping them as they spiral adiabatically into a central swarm. As p → 0, Δp → 0. The resulting cooled muons can lead to an intense muon beam which could be a source for neutrino factories or muon colliders.

3

Jummunt, S., P. Sunwong, S. Prawanta, A. Kwankasem, V. Sooksrimuang, W. Promdee, K. Chaiyasit, P. Aim-O, S. Chunjarean, and S. Klinkhieo. "Development of a solenoid magnet for emittance compensation." Journal of Physics: Conference Series 2653, no. 1 (December 1, 2023): 012034. http://dx.doi.org/10.1088/1742-6596/2653/1/012034.

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Abstract This paper explores the implementation of a solenoid field to achieve electron beam focusing and compensation of transverse emittance, which is generated from photocathode RF gun. An extensive investigation was conducted to determine the optimal solenoid magnetic field required for focusing an electron bunch with a charge of 0.5 nC. A magnetic field strength of 0.25 T was chosen for emittance compensation, enabling the reduction of emittance to below 1.20 mm-mrad at the end of linac. The engineering design of the solenoid magnet for this system is presented in detail, ensuring precise dimensional tolerances within the range of ±30 µm. To ensure its effectiveness and reliability, extensive thermal and mechanical analyses were conducted. Currently, the prototype solenoid magnet is in the fabrication process.

4

ANDERSON, S. G., D. J. GIBSON, F. V. HARTEMANN, J. S. JACOB, A. M. TREMAINE, J. K. LIM, P. FRIGOLA, J. B. ROSENZWEIG, and G. TRAVISH. "PRODUCTION OF FEMTOSECOND PULSES AND MICRON BEAM SPOTS FOR HIGH BRIGHTNESS ELECTRON BEAM APPLICATIONS." International Journal of Modern Physics A 22, no. 22 (September 10, 2007): 3726–35. http://dx.doi.org/10.1142/s0217751x0703738x.

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Current and future applications of high brightness electron beams, which include advanced accelerators and beam-radiation interactions require both transverse and longitudinal beam sizes on the order of tens of microns. Ultra-high density beams may be produced at moderate energy (50 MeV) by compression and subsequent strong focusing of low emittance, photoinjector sources. We describe the implementation of this method used at the PLEIADES inverse-Compton scattering (ICS) x-ray source at LLNL in which the photoinjector-generated beam has been compressed to 300 fsec rms duration using the velocity bunching technique and focused to 20 μm rms size using an extremely high gradient, permanent magnet quadrupole focusing system.

5

Makarov, Vladimir, and Igor Khmelinskii. "Focusing effects of ballistic transverse-quantized excitons in metal nanofilms." Optik 242 (September 2021): 167283. http://dx.doi.org/10.1016/j.ijleo.2021.167283.

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Wu, Bin, Kai Zhou, Shouyan Xu, Changdong Den, Mingyang Huang, Yu Bao, Hangtao Jing, and Xiao Li. "Design and beam dynamics validation of a spiral FFAG accelerator for CSNS-II." Journal of Instrumentation 19, no. 06 (June 1, 2024): T06011. http://dx.doi.org/10.1088/1748-0221/19/06/t06011.

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Abstract The fixed-field alternating gradient (FFAG) accelerator, with its compact structure and the combined advantages of high energy from synchrotrons and high beam intensity from cyclotrons, offers unparalleled benefits in accelerating protons, heavy ions, and short-lived particles such as muons and unstable nuclei. The China Spallation Neutron Source plans to establish an FFAG accelerator with a diameter of 20 meters at the end of the negative hydrogen linac for various purposes, including experiments in nuclear physics and medical applications. For this design, a scaling scheme using spiral magnets as the basic focusing structure is investigated to provide the proton beam with kinetic energy ranging from 300 MeV to 600 MeV. We present the design results for the scaling FFAG accelerator and discuss the optimization of the cell tune. A detailed beam dynamics verification and discussion of the proposed FFAG accelerator lattice are presented using the ray-tracing code Zgoubi, including off-axis optical characteristics, large amplitude transverse motion, and full-cycle longitudinal acceleration. The FFAG accelerator is demonstrated to provide a large transverse and longitudinal acceptance for the tracking beam in the designed lattice. A new simulation code based on Python for the study of FFAG accelerator beam dynamics has been developed, and the corresponding verification results are also presented.

7

Xie, Zhixiong, Yanzhong Yu, and Mingxiang Wu. "Generation of 3D quasi-spherical multi-focus arrays and optical rings using orthogonally superimposed dipole antenna arrays." Journal of Optics 25, no. 10 (August 24, 2023): 105701. http://dx.doi.org/10.1088/2040-8986/acf0d3.

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Abstract This paper proposes a novel method to generate a three-dimensional (3D) quasi-spherical focal point with high longitudinal and transverse resolution in a 4Pi focusing system based on the radiation pattern of the orthogonally superimposed dipole antenna. In this paper, we present generated 3D quasi-spherical multi-focus arrays that are controllable and uniformly distributed and optical rings from the radiation patterns of antenna arrays in different configurations. The results showed that the generated focal point is smaller longitudinally (0.31λ) than transversely (0.41λ). This focal point has the smallest volume (∼0.0273λ 3) found. Moreover, it is highly homogeneous and has a small side lobe. The polarization at the center of the focal point is purely circular. The resulting 3D focal fields can be easily tailored by adjusting the modulation parameters of the orthogonally superimposed dipole arrays. Manipulating 3D optical focal fields with pre-defined characteristics of quasi-spherical focal points has a high degree of freedom. Many potential applications exist in arbitrarily oriented particle capture and guidance, micromanipulation, optical capture, and 3D optical data storage.

8

Rendell, M., O. Klochan, A. Srinivasan, I. Farrer, D. A. Ritchie, and A. R. Hamilton. "Transverse magnetic focussing of heavy holes in a (100) GaAs quantum well." Semiconductor Science and Technology 30, no. 10 (September 14, 2015): 102001. http://dx.doi.org/10.1088/0268-1242/30/10/102001.

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Man, Zhongsheng, Xiaoyu Li, Shuoshuo Zhang, Zhidong Bai, Yudong Lyu, Jinjian Li, Xiaolu Ge, Yuping Sun, and Shenggui Fu. "Manipulation of the transverse energy flow of azimuthally polarized beam in tight focusing system." Optics Communications 431 (January 2019): 174–80. http://dx.doi.org/10.1016/j.optcom.2018.09.028.

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Božović, Ivan, Xi He, Anthony T. Bollinger, and Roberta Caruso. "Is Nematicity in Cuprates Real?" Condensed Matter 8, no. 1 (January 10, 2023): 7. http://dx.doi.org/10.3390/condmat8010007.

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In La2-xSrxCuO4 (LSCO), a prototype high-temperature superconductor (HTS) cuprate, a nonzero transverse voltage is observed in zero magnetic fields. This is important since it points to the breaking of the rotational symmetry in the electron fluid, the so-called electronic nematicity, presumably intrinsic to LSCO (and other cuprates). An alternative explanation is that it arises from extrinsic factors such as the film’s inhomogeneity or some experimental artifacts. We confront this hypothesis with published and new experimental data, focusing on the most direct and sensitive probe—the angle-resolved measurements of transverse resistivity (ARTR). The aggregate experimental evidence overwhelmingly refutes the extrinsic scenarios and points to an exciting new effect—intrinsic electronic nematicity.

11

Bogacz, S. A., and D. B. Cline. "A μ+μ- Quantum Collider using Novel Crystal-Based Accelerator Components." International Journal of Modern Physics A 12, no. 18 (July 20, 1997): 3181–92. http://dx.doi.org/10.1142/s0217751x97001675.

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We outline a concept of a 250 × 250 GeV μ+ μ- collider that uses bent crystals for beam confinement and steering instead of conventional magnets. The collider ring is based on a novel bending-focusing crystal cell. Beam optics of the proposed model cell has all the features of the alterating gradient FODO cell. Furthermore, alternating (horizontal-vertical) focusing provides unique betatron phase stability in both planes, while bending of particle trajectories due to crystal curvature is fully achromatic. We also explore the ionization energy loss of channeling muons interacting with the electron gas in a crystal channel as a possible cooling mechanism. Finally, a use of low Z binary crystals (such as LiF) for final focus at the interaction point is proposed. Bringing the μ+μ- into collision inside a crystal channel results in quantum confinement at the collision point. For such a collider the number of required μ± may be very low (~108μ per pulse), so that this collider has few problems from μ → e backgrounds or heating, which is a virtue of paramount importance. A low intensity hadronic μ± source (p + A → π → μ) can be utilized provided that an effective method of fast muon cooling is used. For example, the use of frictional cooling for low energy μ± beams could initially reduce the longitudinal phase–space, before the final transverse cooling is applied. Here, we outline such a "crystal cooler" that explores ionization energy loss in the ultrastrong focusing environment of a crystal channel. Employing all the above-mentioned novel crystal-based accelerator components, a possible luminosity of about 1032 cm-2 sec-1, is estimated for the proposed quantum collider. We also discuss a list of problems one needs to solve in order to make such a collider a real possibility.

12

Прокопов, Павел, Pavel Prokopov, Юрий Захаров, Yuriy Zakharov, Владимир Тищенко, Vladimir Tishchenko, Эдуард Бояринцев, et al. "On the possibility for laboratory simulation of generation of Alfvén disturbances in magnetic tubes in the solar atmosphere." Solar-Terrestrial Physics 2, no. 1 (June 1, 2016): 19–33. http://dx.doi.org/10.12737/19859.

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The paper deals with generation of Alfvén plasma disturbances in magnetic flux tubes through exploding laser plasma in magnetized background plasma. Processes with similar effect of excitation of torsion-type waves seem to provide energy transfer from the solar photosphere to the corona. The studies were carried out at experimental stand KI-1 representing a high-vacuum chamber 1.2 m in diameter, 5 m in length, external magnetic field up to 500 G along the chamber axis, and up to 2·10–6 Torr pressure in operating mode. Laser plasma was produced when focusing the CO2 laser pulse on a flat polyethylene target, and then the laser plasma propagated in θ-pinch background hydrogen (or helium) plasma. As a result, the magnetic flux tube 15–20 cm in radius was experimentally simulated along the chamber axis and the external magnetic field direction. Also, the plasma density distribution in the tube was measured. Alfvén wave propagation along the magnetic field was registered from disturbance of the magnetic field transverse component Bφ and field-aligned current Jz. The disturbances propagate at a near-Alfvén velocity 70–90 km/s and they are of left-hand circular polarization of the transverse component of magnetic field. Presumably, the Alfvén wave is generated by the magnetic laminar mechanism of collisionless interaction between laser plasma cloud and background. A right-hand polarized high-frequency whistler predictor was registered which propagated before the Alfvén wave at a velocity of 300 km/s. The polarization direction changed with the Alfvén wave coming. Features of a slow magnetosonic wave as a sudden change in background plasma concentration along with simultaneous displacement of the external magnetic field were found. The disturbance propagates at ~20–30 km/s velocity, which is close to that of ion sound at low plasma beta value. From preliminary estimates, the disturbance transfers about 10 % of the original energy of laser plasma.

13

Zhou, Shun, Yechuan Zhu, Shaobo Ge, Fei Xie, Na Jin, and Weiguo Liu. "Impact of Fabrication and Operation Errors on Super-Focusing Performance of a Nanoslit-Based Metalens." Journal of Nanoelectronics and Optoelectronics 16, no. 7 (July 1, 2021): 1115–19. http://dx.doi.org/10.1166/jno.2021.3057.

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Metasurfaces with optical manipulation at subwavelength resolution show promises for developing ultrathin and flat optical components, attracting great interest from the optical scientific community. In our recent work, a metalens has demonstrated a special capability of quasi-far-field super-resolution focusing, which comprised a metallic nanoslit array with the incidence of a transverse-electric (TE) polarized light. In this paper, in order to guide practical fabrication and operation of a device, we perform a study on the metalens to analyze the impact of many imperfections on the super-resolution focusing capability. We take fabrication and operation errors into account, including errors in nanoslit width, metal film thickness, operating wavelength, polarization and incident angle of incident light. Numerical results illustrate that the sensitivity of the metalens focusing performance to each error is different. To be specific, the focusing performance of the metalens is considerably susceptible to the error in the incidence angle. Therefore, we not only need to fabricate the metalens device precisely, but also need to ensure that the working conditions agree well with the design, so as to achieve the desired focusing performance. Our research offers a valuable guide for the realization of the super-resolution focusing technology in practice.

14

Lavrov, L. M., A. V. Bessarab, D. I. Martsovenko, F. A. Starikov, A. A. Andreev, and K. Yu Platonov. "Transverse scattering of radiation upon focusing of pump laser beam to line in experiments on X-ray laser." Optics and Spectroscopy 111, no. 2 (August 2011): 184–90. http://dx.doi.org/10.1134/s0030400x11080200.

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15

Walia, Keshav. "Enhanced Brillouin scattering of gaussian laser beam in collisional plasma: Moment theory approach." Journal of Nonlinear Optical Physics & Materials 23, no. 01 (March 2014): 1450011. http://dx.doi.org/10.1142/s0218863514500118.

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In the present paper, enhanced Brillouin scattering of a gaussian laser beam in a collisional plasma has been investigated with the help of moment theory approach. The pump wave (ω0, k0) interacts with pre-excited ion-acoustic wave (ω, k), thereby generating a back-scattered wave (ω0 - ω, k0 - k). As a specific case, back scattering for which k ≃ 2k0 has been discussed. Due to nonuniform heating, collisional nonlinearity arises, which leads to redistribution of carriers. As a result background plasma density profile in a direction transverse to pump beam axis is modified. Consequently, the pump beam becomes self-focused and in turn leads focusing of ion-acoustic wave and back-scattered wave under appropriate conditions. It is further observed from the analysis that focusing of waves greatly enhances the SBS back-reflectivity.

16

Chen, G. X., W. Ma, C. Y. Wang, Z. Y. Zhang, L. P. Zou, Z. Yang, J. H. Yang, and L. Lu. "Design and beam dynamics simulation of an 8 MeV compact accelerator-driven neutron source." Journal of Instrumentation 19, no. 05 (May 1, 2024): P05002. http://dx.doi.org/10.1088/1748-0221/19/05/p05002.

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Abstract A compact accelerator-driven neutron source is proposed at Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, called Sun Yat-Sen University Proton Accelerator Facility (SYSU-PAFA). The proton accelerator is composed of a proton electron cyclotron resonance source, a four-vane radio frequency quadrupole (RFQ), and an alternative phase focusing drift tube linac (APF-DTL). It can accelerate 10 mA proton beam to 8 MeV. Due to the high current, beam matching is particularly important. In order to achieve beam matching between various components, beam transport sections are needed. The beam transport line is divided into three segments. The Low Energy Beam Transport (LEBT) ensures that the beam parameters are matched before entering the RFQ. The Medium Energy Beam Transport (MEBT) segment efficiently transfers the beam between the RFQ and DTL. The High Energy Beam Transport (HEBT) focuses on transporting the beam to the targets. The design goal of beam transport line is as short as possible while ensuring high efficiency of beam transportation. SYSU-PAFA has an overall transmission efficiency of 99%, with optimal transverse matching conditions between beam transport and RFQ or DTL accelerators. The efficient use of solenoids and magnets allows for a compact transmission section, resulting in a total length of 13.6 meters, shorter than most accelerators at the same beam energy. This paper will provide the detailed beam dynamics of the compact accelerator.

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WALIA, KESHAV, and ARVINDER SINGH. "EFFECT OF SELF-FOCUSING ON STIMULATED RAMAN SCATTERING BY A GAUSSIAN LASER BEAM IN COLLISIONAL PLASMA: MOMENT THEORY APPROACH." Journal of Nonlinear Optical Physics & Materials 22, no. 03 (September 2013): 1350030. http://dx.doi.org/10.1142/s0218863513500306.

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In the present paper, the effect of self-focusing on stimulated Raman scattering (SRS) process by a Gaussian laser beam in collisional plasma is investigated. Due to non-uniform heating, collisional nonlinearity arises, which leads to redistribution of carriers. As a result of which, background plasma density profile in a direction transverse to pump beam axis is modified. This modification affects the incident laser beam, electron plasma wave and back-scattered beam. Nonlinear differential equations for the beam width parameters of the main beam, electron plasma wave, back-scattered wave have been set up by taking full nonlinear part of the dielectric constant of collisional plasma with the help of moment theory approach and are solved numerically by Runge–Kutta method. It is observed from the analysis that focusing of waves greatly enhances the SRS reflectivity.

18

Varin, Charles, Michel Piché, and Miguel A. Porras. "Analytical calculation of the longitudinal electric field resulting from the tight focusing of an ultrafast transverse-magnetic laser beam." Journal of the Optical Society of America A 23, no. 8 (August 1, 2006): 2027. http://dx.doi.org/10.1364/josaa.23.002027.

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Wang, Dengpan, Kaiyue Liu, Xiaofeng Li, Guangming Wang, Shiwei Tang, and Tong Cai. "Bifunctional spoof surface plasmon polariton meta-coupler using anisotropic transmissive metasurface." Nanophotonics 11, no. 6 (February 2, 2022): 1177–85. http://dx.doi.org/10.1515/nanoph-2021-0761.

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Abstract Tailoring the wavefronts of spoof surface plasmon polaritons (SSPPs) at will, especially with multifunctional integration, is of great importance in near-field photonics. However, conventional SSPP devices suffer from the issues of bulk configurations, limited functionalities, and single operating modes, which are unfavorable for electromagnetic (EM) integration. Here, a novel scheme is proposed to design bifunctional SSPP meta-devices based on the polarization dependent property via satisfying the comprehensive phase distributions and multi-mode momentum matching in a transmission geometry. As proof of the concept, we experimentally demonstrate a bifunctional SSPP meta-device in the microwave regime that can convert incident x- and y-polarized waves to transverse magnetic (TM)-mode SSPP Bessel beams and transverse electric (TE)-mode SSPP focusing beams, respectively. Our findings open a door to achieve near-field manipulation of SSPPs with multi-function and multi-mode integration, which can stimulate the applications of SSPP functional devices, such as near-field sensing, imaging, and on-chip photonics.

20

Pal, Sushanta Kumar, Rakesh Kumar Singh, and P. Senthilkumaran. "Focal intensity landscapes of tightly focused spatially varying bright ellipse fields." Journal of Optics 24, no. 4 (March 11, 2022): 044013. http://dx.doi.org/10.1088/2040-8986/ac56b7.

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Abstract Vector vortex beams play an important role in tailoring tightly focused fields by creating an additional longitudinal component at the focal plane. Until now, mainly focusing properties of fundamental, higher order vector fields and negative indexed ellipse fields have been investigated. In this paper we numerically analyze tight focusing behaviour of ellipse fields embedding C-point singularities of index I C = ± 1 2 , I C = ± 1 , I C = ± 3 2 and I C = ± 2 . We show that both the sign and absolute value of C-point index (I C ) of the ellipse fields play an important role in tailoring the focal intensity landscapes. For negative index C-points the intensity distribution of the longitudinal components show symmetries that correspond to the number of separatrices present in the polarization distribution. At the focal plane, both transverse and longitudinal components of the ellipse fields are found to be embedded with phase singularities. These ellipse fields can be useful in advanced microscopy for shaping the focus of light fields for various applications.

21

Kurseeva, Valeria, Stanislav Tikhov, and Dmitry Valovik. "Electromagnetic wave propagation in a layer with power nonlinearity." Journal of Nonlinear Optical Physics & Materials 28, no. 01 (March 2019): 1950009. http://dx.doi.org/10.1142/s0218863519500097.

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The paper focuses on a problem that describes propagation of transverse-electric (TE) waves in a plane dielectric waveguide filled with nonlinear medium. The nonlinearity is characterized by the power term [Formula: see text], where [Formula: see text], [Formula: see text] are constants and [Formula: see text] is the electric term of the guided electromagnetic field. The layer is located between two half-spaces filled with linear media having constant permittivities. It is proved that the nonlinear problem has infinitely many propagation constants (PCs), whereas the corresponding linear problem has only a finite number of them. The nonlinearity leads to the occurrence of infinitely many nonperturbative solutions of the nonlinear problem. Results of the paper show that the power nonlinearity (for any [Formula: see text]) and Kerr nonlinearity (for [Formula: see text]) produce qualitatively similar outcomes. In addition, the found results allow one to study very important cases of quintic, septimal, etc. nonlinear permittivities in the focusing regime.

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Savignac, Laurence, John M. Griffin, and Steen B. Schougaard. "New Insight into Li⁺ Dynamics in Lithium Bimetal Phosphate." Journal of The Electrochemical Society 169, no. 1 (January 1, 2022): 010510. http://dx.doi.org/10.1149/1945-7111/ac4544.

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Substitution of iron by other transition metals within the remarkably stable olivine framework is of interest considering the expected gain in energy density. However, manganese rich olivine materials suffer from sluggish redox kinetics, leading to electrochemical performances at high current densities which are below expectations. The source of the kinetic limitations is not clear, with multiple processes having been proposed, including low bulk electronic conductivity, structural instability of Mn3+ and a phase transition mechanism. This study employed 7Li MAS NMR relaxation techniques to indirectly probe Li+ dynamics using various stoichiometry of chemically prepared Li x MnyFe1-yPO4 (0 ≤ (x, y) ≤ 1). Focusing on the particle level, the aim was to understand how the different crystal phases, alongside the Mn structural contribution, influence Li+ transport at each stage of the oxidation process. Significantly, the formation of an olivine solid solution with vacancies within this progression gave rise to a faster 7Li transverse relaxation derived from superior Li+ motion.

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Pang, Xiaoyan, Weiwei Xiao, Han Zhang, Chen Feng, and Xinying Zhao. "X-type vortex and its effect on beam shaping." Journal of Optics 23, no. 12 (November 12, 2021): 125604. http://dx.doi.org/10.1088/2040-8986/ac34e7.

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Abstract In this article we propose a new type of optical vortex, the X-type vortex. This vortex inherits and develops the conventional noncanonical vortex, i.e. it no longer has a constant phase gradient around the center, while the intensity keeps invariant azimuthally. The strongly focusing properties of the X-type vortex and its effect on the beam shaping in three-dimensional (3D) fields are analyzed. The interesting phenomena, which cannot be seen in canonical vortices, are observed, for instance the ‘switch effect’ which shows that the intensity pattern can switch from one transverse axis to another in the focal plane by controlling the phase gradient parameter. It is shown that by adjusting the phase gradient of this vortex, the focal field can have marvelous patterns, from the doughnut shape to the shapes with different lobes, and the beam along propagation direction will form a twisting shape in 3D space with controllable rotation direction and location. The physical mechanisms underlying the rule of the beam shaping are also discussed, which generally say that the phase gradient of the X-type vortex, the orbital angular momentum, the polarization and the ‘nongeneric’ characteristic contribute differently in shaping fields. This new type of vortex may supply a new freedom for tailoring 3D optical fields, and our work will pave a way for exploration of new vortices and their applications.

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Wu, Hua-Qin, Hao-Yu Wang, Wen-Ming Xie, Shu-Lian Wu, Zhi-Fang Li, Xiao-Man Zhang, and Hui Li. "Scanning photoacoustic imaging of submucosal gastric tumor based on a long focused transducer in phantom and in vitro experiments." Journal of Innovative Optical Health Sciences 12, no. 03 (May 2019): 1950011. http://dx.doi.org/10.1142/s1793545819500111.

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Photoacoustic imaging, which can provide the maximum intensity contrast in tissue depth imaging without ionizing radiation, will be a promising imaging trend for tumor detection. In this paper, a column diffusion fiber was employed to carry a pulsed laser for irradiating stomach directly through esophagus based on the characteristics of gastric tissue structure. A long focused ultrasonic transducer was placed outside the body to detect photoacoustic signals of gastric tissue. Phantom and in vitro experiments of submucosal gastric tumors were carried out to check the sensitivity of scanning photoacoustic tomography system, including the lateral and longitudinal resolution of the system, sensitivity of different absorption coefficient in imaging, capability of transversal detection, and probability of longitudinal detection. The results demonstrate that our innovative technique can improve the parameters of imaging. The lateral resolution reaches 2.09[Formula: see text]mm. Then a depth of 5.5[Formula: see text]mm with a longitudinal accuracy of 0.36[Formula: see text]mm below gastric mucosa of early gastric cancer (EGC) has been achieved. In addition, the optimal absorption coefficient differences among absorbers of system are 3.3–3.9 times. Results indicate that our photoacoustic imaging (PAI) system, is based on a long focusing transducer, can provide a potential application for detecting submucosal EGC without obvious symptoms.

25

Sala, Filip. "Beam splitting in chiral nematic liquid crystals." Photonics Letters of Poland 10, no. 4 (December 31, 2018): 109. http://dx.doi.org/10.4302/plp.v10i4.867.

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By lunching the beam into the chiral nematic liquid crystals it is possible to achieve a non-diffractive beam similar to a soliton. This effect is caused by the molecular reorientation i.e. nonlinear response of the material forming the areas of higher refractive index. Diffraction is suppressed by the focusing effect. For appropriate launching conditions it is also possible to achieve a beam which splits into two or more separate beams. Such phenomenon is discussed in this article and analyzed theoretical. To model this effect Fully Vectorial Beam Propagation Method coupled with the Frank-Oseen elastic theory is used. Simulations are performed for various input beam powers, widths, polarization angles and launching positions. Full Text: PDF ReferencesG. Assanto and M. A. Karpierz, "Nematicons: self-localised beams in nematic liquid crystals", Liq. Cryst. 36, 1161–1172 (2009) CrossRef G. Assanto, Nematicons: Spatial Optical Solitons in Nematic Liquid Crystals, John Wiley & Sons Inc. Hoboken, New Jersey (2013) DirectLink A. Piccardi, A. Alberucci, U. Bortolozzo, S. Residori, and G. Assanto, "Soliton gating and switching in liquid crystal light valve", Appl. Phys. Lett. 96, 071104 (2010). CrossRef D. Melo, I. Fernandes, F. Moraes, S. Fumeron, and E. Pereira, "Thermal diode made by nematic liquid crystal", Phys. Lett. A 380, 3121 – 3127 (2016). CrossRef U. Laudyn, M. Kwaśny, F. A. Sala, M. A. Karpierz, N. F. Smyth, G. Assanto, "Curved optical solitons subject to transverse acceleration in reorientational soft matter", Sci. Rep. 7, 12385 (2017) CrossRef M. Kwaśny, U. A. Laudyn, F. A. Sala, A. Alberucci, M. A. Karpierz, G. Assanto, "Self-guided beams in low-birefringence nematic liquid crystals", Phys. Rev. A 86, 013824 (2012) CrossRef F. A. Sala, M. M. Sala-Tefelska, "Optical steering of mutual capacitance in a nematic liquid crystal cell", J. Opt. Soc. Am. B. 35, 133-139 (2018) CrossRef U. A. Laudyn, A. Piccardi, M. Kwasny, M. A. Karpierz, G. Assanto, "Thermo-optic soliton routing in nematic liquid crystals", Opt. Lett. 43, 2296-2299 (2018) CrossRef F. A. Sala, M. M. Sala-Tefelska, M. J. Bujok, J. "Influence of temperature diffusion on molecular reorientation in nematic liquid crystals", Nonlinear Opt. Phys. Mater. 27, 1850011 (2018) CrossRef I-C Khoo Liquid crystals John Wiley & Sons, Inc (2007) DirectLink P. G. de Gennes, J. Prost, The Physics of Liquid Crystals, Clarendon Press (1995) DirectLink U. A. Laudyn, P. S. Jung, M. A. Karpierz, G. Assanto, "Quasi two-dimensional astigmatic solitons in soft chiral metastructures", Sci. Rep. 6, 22923 (2016) CrossRef J. Beeckman, A. Madani, P. J. M. Vanbrabant, P. Henneaux, S-P. Gorza, M. Haelterman, "Switching and intrinsic position bistability of soliton beams in chiral nematic liquid crystals", Phys. Rev. A 83, 033832 (2011) CrossRef A. Madani, J. Beeckman, K. Neyts, "An experimental observation of a spatial optical soliton beam and self splitting of beam into two soliton beams in chiral nematic liquid crystal", Opt. Commun. 298–299, 222-226, (2013) CrossRef G. D. Ziogos, E. E. Kriezis, "Modeling light propagation in liquid crystal devices with a 3-D full-vector finite-element beam propagation method", Opt. Quant. Electron 40, 10 (2008) CrossRef F. A. Sala, M. A. Karpierz, "Chiral and nonchiral nematic liquid-crystal reorientation induced by inhomogeneous electric fields", J. Opt. Soc. Am. B 29, 1465-1472 (2012) CrossRef F. A. Sala, M. A. Karpierz, "Modeling of molecular reorientation and beam propagation in chiral and non-chiral nematic liquid crystals", Opt. Express 20, 13923-13938 (2012) CrossRef F. A. Sala, "Design of false color palettes for grayscale reproduction", Displays, 46, 9-15 (2017) CrossRef

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Takale, Prasad, Kalyani Khandale, Sanyogita Patil, Sandip Patil, and Mansing Takale. "Study of propagation of skew cosh Gaussian laser beam in attenuated magneto plasma." Modern Physics Letters B, July 26, 2023. http://dx.doi.org/10.1142/s0217984923501853.

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Self-focusing of a laser beam is one of the major consequences of nonlinear interaction of laser with plasma. In this paper, self-focusing of skew cosh Gaussian (skew-ChG) laser beam is studied in anisotropic, collisional plasma where in externally exponentially decreasing magnetic field is applied. Skewness parameters in the field profile of skew-ChG laser beam eventually determine intensity profile of the beam. The symmetry in skewness parameter in two transverse directions simplifies the calculations considerably. Second order, nonlinear, ordinary, coupled differential equations for Beam Width Parameters (BWP) are obtained using Akhmanovs approach under Wentzel–Kramers–Brillouin (WKB) and paraxial approximations which are solved numerically. For given amplitude of applied magnetic field, attenuated oscillatory self-focusing is observed with respect to change in attenuation coefficient.

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赵良超. "Transmission ratio and beam acceptance of the SESRI300MeV synchrotron injection line." Acta Physica Sinica, 2022, 0. http://dx.doi.org/10.7498/aps.71.20212112.

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SESRI300MeV synchrotron in Harbin Institute of Technology is now under construction and all the equipment have been installed and tested. Before beam commission beginning, beam transport through the injection line is simulated with a full dimension model by tracewin code. Field distribution of RF cavities are calculated with CST and results are substituted in to the tracewin code to generate accurate results. Envelop mode and multi-particles mode are used in the beam simulation with two typical beams (2H%2B and 209Bi32%2B, the lightest beam and the heaviest beam). Both beams are accelerated from 4keV/u to 2MeV/u by a RFQ cavity and two IH-DTL cavities. Then 2H%2B beam is stripped to proton beam by a carbon foil and accelerated to 5.6MeV with the third IH-DTL cavity. Simulation results show that the strength of the magnet and the acceleration field are proportional to the mass charge ratio. Beam transmission ratio and the injection line acceptance are inverse proportional to the beam transverse emittance. 209Bi32%2B beam transmission ratio and beam acceptance(energy spread less than ±0.2%) are 72.16% and 46.72% with transverse emittanceε=0.12πmm·mrad(ECR source output) and ε=0.4πmm·mrad(RFQ output). 2H%2B beam transmission ratio and beam acceptance are 24.19% and 17.89% with ε=0.2πmm·mrad (ECR source output) and ε=0.5ππmm·mrad (RFQ output). In order to obtain high transmission ratio and beam acceptance, transverse emittance should be limited to 0.1πmm·mrad after the RFQ. With this limitation, 209Bi32%2B beam transmission ratio and the acceptance are increased to 96.68% and 92.63%, 2H%2B beam transmission ratio and the acceptance are increased to 74.40% and 68.18%. If two additional quadrupole magnets are added, the 2H%2B beam transmission ratio and beam acceptance can be increased to 90.73% and 83.61%, which will fulfill the long-time operation request. Phase space change process shows that loss of 209Bi32%2B beam is mainly caused by longitudinal defocusing (energy spread and phase width spread), loss of proton beam is caused both by longitudinal defocusing and transverse defocusing (beam envelop spreading), that is why two additional focusing magnets should be added in proton beam acceleration. Results also show that by using field distribution calculation in the simulation process, more influences of the cavity design details can be confirmed, like beam off-axis caused by dipole field in the IH-DTL cavity and beam loss caused by unperfect field in the RFQ. Tracking with field distribution is shown to be a useful method to link the cavity design process, beam line design process, and beam commission process.

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Usaj, Gonzalo, and C. Balseiro. "Transverse electron focusing in systems with spin-orbit coupling." Physical Review B 70, no. 4 (July 2004). http://dx.doi.org/10.1103/physrevb.70.041301.

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Reynoso, A., Gonzalo Usaj, and C. A. Balseiro. "Detection of spin polarized currents in quantum point contacts via transverse electron focusing." Physical Review B 75, no. 8 (February 23, 2007). http://dx.doi.org/10.1103/physrevb.75.085321.

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Kormányos, Andor. "Semiclassical study of edge states and transverse electron focusing for strong spin-orbit coupling." Physical Review B 82, no. 15 (October 18, 2010). http://dx.doi.org/10.1103/physrevb.82.155316.

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Lu, Guangwei, Yaojun Li, Xichen Hu, Siyu Chen, Hao Xu, Mingyang Zhu, Wenchao Yan, and Liming Chen. "Divergence Angle Consideration in Energy Spread Measurement for High-Quality Relativistic Electron Beam in LWFA." Chinese Physics B, February 28, 2024. http://dx.doi.org/10.1088/1674-1056/ad2dcb.

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Abstract The thorough exploration of the transverse quality represented by divergence angle has been lacking yet in the energy spread measurement of the relativistic electron beam for laser wakefield acceleration (LWFA). In this paper, we address this gap by numerical simulations based on the experimental data. It suggests that in a C-shape magnet magnetic field with the beam focusing effect, considering the divergence angle would result in an increase in the full width at half maxima (FWHM) of the electron density distribution in a uniformly isotropic manner, while the length-to-width ratio decreases. This indicates that the energy spread obtained from the electron deflection distance is smaller than the actual value, regardless of the divergence angle. A promising and efficient way to accurately correct the value is present by considering the divergence angle (for instance, for an electron beam with a length-to-width ratio of 1.12, the energy spread correct from 1.2% to 1.5%), providing a reference for the high-quality electron beam source development.

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Kumar, Ram Nandan, Jeeban Kumar Nayak, Subhasish Dutta Gupta, Nirmalya Ghosh, and Ayan Banerjee. "Probing Dual Asymmetric Transverse Spin Angular Momentum in Tightly Focused Vector Beams in Optical Tweezers." Laser & Photonics Reviews, November 23, 2023. http://dx.doi.org/10.1002/lpor.202300189.

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AbstractThe spin‐orbit interaction (SOI) of light generated by tight focusing in optical tweezers is regularly employed in generating angular momentum ‐ both spin and orbital ‐ the effects being extensively observed in trapped mesoscopic particles. Specifically, the transverse spin angular momentum (TSAM), which arises due to the longitudinal component of the electromagnetic field generated by tight focusing is of special interest, both in terms of fundamental studies and associated applications. This study provides an effective and optimal strategy for generating TSAM in optical tweezers by tightly focusing first‐order radially and azimuthally polarized vector beams with no intrinsic angular momentum (AM) into a refractive index stratified medium. The choice of such input fields ensures that the longitudinal spin angular momentum (LSAM) arising from the electric (magnetic) field for the radial (azimuthal) polarization is zero. As a result, the effects of the electric and magnetic TSAM are exclusively observed separately in the case of input first‐order radially and azimuthally polarized vector beams on single optically trapped birefringent particles. This research opens up new and simple avenues for exotic and complex particle manipulation in optical tweezers.

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Saini, Omshankar, Vivek Venkataraman, and Joyee Ghosh. "Impact of focusing and polarization inhomogeneity on SHG in type-II ppKTP." Journal of Optics, March 22, 2023. http://dx.doi.org/10.1088/2040-8986/acc672.

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Abstract We study the effects of pump beam focusing and polarization inhomogeneity on second-harmonic generation (SHG) in a 3-cm long type-II ppKTP crystal. Focusing leads to an asymmetry in the SHG output power around the phase-matching temperature (PMT), along with a shift of the PMT to a lower temperature. Theoretical predictions are experimentally verified for different focusing parameters at various pump wavelengths, showing maximum SHG of 0.24%/W (close to optimal focusing). Further, an inhomogeneous polarizationacross the pump beam cross-section is theoretically predicted to break up the SHG transverse (intensity) profile into several lobes, resulting in an overall decrease in the total output power. We experimentally show that a radially/azimuthally polarized pump beam (generated via a Q-plate) results in a four-lobed SHG similar to the Hermite-Gaussian HG11 mode with an optimal focusing parameter that is four times higher than that for the homogeneously polarized pump.

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Herrera, Isael, and Pedro Quinto-Su. "Measurement of structured tightly focused beams with classical interferometry." Journal of Optics, January 18, 2023. http://dx.doi.org/10.1088/2040-8986/acb44c.

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Abstract We report the first classic interferometric measurement of the full field of propagating tightly focused vector beams (NA up to $1.23$) across areas of $\sim 3 \lambda \times 3 \lambda - 7 \lambda \times 7 \lambda $. This approach outperforms near field measurements of non paraxial propagating beams because it is compatible with large power imbalances across the polarization components and low light intensities. Also, intricate subwavelength structures are resolved due to the exact mapping of the transverse field components by the microscope. Prior to focusing, the structured laser light has a linear or circular polarization state and an arbitrary 2D spatial phase. The transverse polarization components are extracted directly from 12 interferograms using 4 step interferometry, while the longitudinal component is extracted from the measured transverse fields with Gauss law. Different structured propagating vectorial beams are measured to demonstrate that the method works for any field geometry. The measurements are compared to simulations with normalized cross correlations that yield mean values $\geq 0.8$, confirming good agreement.

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Shen, Jian, Yong Zhang, Yihang Dong, Zihan Xu, Jian Xu, Xueling Quan, Xihua Zou, and Yikai Su. "Ultra-broadband on-chip beam focusing enabled by GRIN metalens on silicon-on-insulator platform." Nanophotonics, July 14, 2022. http://dx.doi.org/10.1515/nanoph-2022-0242.

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Abstract Metalens has emerged as an important optical block in free-space optical systems, which shows excellent performance. Even the metalens based on gradient index (GRIN) profiles can be implemented for on-chip beam focusing behavior. However, for most previous schemes, the GRIN metalenses can only achieve on-chip beam focusing behavior in one dimension, which limits their applications in low-loss waveguide interconnecting or fiber-to-chip coupling. In this paper, an on-chip half Maxwell’s fisheye lens based on GRIN profiles with subwavelength features, integrated with silicon waveguides, is experimentally demonstrated. Benefitting from the index distribution and beam focusing characteristics of the half Maxwell’s fisheye lens, an on-chip beam transforming can be achieved for transverse electric (TE) fundamental mode in two waveguides with different heights and widths. The simulated 1 dB bandwidth can reach 1100 nm, which exhibits great prospects in integrated photonic circuits. The measured insertion loss of an on-chip 5.4 μm-length lens is less than 1 dB to connect a 220 nm-height, 8 μm-wide waveguide, and a 60 nm-height, 0.5 μm-wide waveguide in the wavelength range of 1280–1620 nm.

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Xie, Suxia, Siyi Sun, Zhijian Li, Jingcheng Yang, Weiwei Shen, and Xin Guan. "Manipulation of the multiple bound states in the continuum and slow light effect in the all-dielectric metasurface." Journal of Physics D: Applied Physics, June 19, 2023. http://dx.doi.org/10.1088/1361-6463/acdf6a.

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Abstract All-dielectric metasurface with ultra-high quality resonances underpinned by bound states in the continuum (BICs) have attracted lots of attention in recent years for they enable new methods of wavefront control and light focusing. We study a metasurface composed of one transverse nanohole and two identical vertical nanoholes in one lattice, which supports both symmetry-protected and accidental BICs (at-Γ and off-Γ BICs). Based on the destructive interference between the surface states from the transverse nanohole element and the identical vertical nanoholes element, two at -Γ BICs emerge, and they turn into quasi-BICs by rotating the electric field polarization direction of the incident plane wave from Ex to Ey. The off-Γ BICs come from destructive interference from different radiation channels, which are influenced by the in-plane structural parameters symmetry insignificantly. Two at-Γ BICs and one off-Γ BIC of the metasurface all have ultra-high Q-factors (exceeding 106, 104, and 106, respectively), which means much in the application of biosensors. Especially, this nanostructure has outstanding ultra-slow light properties at BICs, with a group index about 106, which underpin a new generation of flat-optics slow light devices.

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Guo, Yinghui, Shicong Zhang, Mingbo Pu, Qiong He, Jinjin Jin, Mingfeng Xu, Yaxin Zhang, Ping Gao, and Xiangang Luo. "Spin-decoupled metasurface for simultaneous detection of spin and orbital angular momenta via momentum transformation." Light: Science & Applications 10, no. 1 (March 25, 2021). http://dx.doi.org/10.1038/s41377-021-00497-7.

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AbstractWith inherent orthogonality, both the spin angular momentum (SAM) and orbital angular momentum (OAM) of photons have been utilized to expand the dimensions of quantum information, optical communications, and information processing, wherein simultaneous detection of SAMs and OAMs with a single element and a single-shot measurement is highly anticipated. Here, a single azimuthal-quadratic phase metasurface-based photonic momentum transformation (PMT) is illustrated and utilized for vortex recognition. Since different vortices are converted into focusing patterns with distinct azimuthal coordinates on a transverse plane through PMT, OAMs within a large mode space can be determined through a single-shot measurement. Moreover, spin-controlled dual-functional PMTs are proposed for simultaneous SAM and OAM sorting, which is implemented by a single spin-decoupled metasurface that merges both the geometric phase and dynamic phase. Interestingly, our proposed method can detect vectorial vortices with both phase and polarization singularities, as well as superimposed vortices with a certain interval step. Experimental results obtained at several wavelengths in the visible band exhibit good agreement with the numerical modeling. With the merits of ultracompact device size, simple optical configuration, and prominent vortex recognition ability, our approach may underpin the development of integrated and high-dimensional optical and quantum systems.

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Zhang, Xiliang, Yanwen Hu, Xin Zhang, Zhen Li, Zhenqiang Chen, and Shenhe Fu. "On‐Demand Subwavelength‐Scale Light Sculpting Using Nanometric Holograms." Laser & Photonics Reviews, September 13, 2023. http://dx.doi.org/10.1002/lpor.202300527.

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AbstractSpatially or temporally structured light has attracted considerable attention for its intriguing beam characteristics, which have found extensive applications in classical and quantum optics. Extending structured light from macroscale and microscale to nanometricscale brings more prospects both for fundamental and applied science. However, sculpting light at the subwavelength scale remains a challenge since its transverse structure is fragile in the nanometric scale. Here a novelholography for arbitrary light sculpting at the subwavelength scale is demonstrated. A wave phenomenon of diffractive focusing from an amplitude‐only nanometric (50‐nm‐thick) film is introduced, and use of the induced high‐spatial‐frequency waves as carriers to encode information of an object is considered. Using this technique, nanometric holograms are designed and fabricated for generating the well‐defined eigen modes including the zero‐order Bessel beam, vortex beam, vector beam, Airy beam, as well as an arbitrary light pattern, with feature sizes on the deep‐subwavelength scale. The broadband performance of the hologram is examined, and a white‐light nondiffracting beam at the deep‐subwavelength scale is realized. This demonstration paves a way toward on‐demand light sculpting at the nanometric scale, which may find applications such as optical super‐resolution imaging, nanoparticle manipulation, and precise measurements.

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Da, Haixia, and Huapeng Ye. "Strong and controlled photonic spin Hall effect in a van der Waals semiconducting transition metal oxide slab." Journal of Physics D: Applied Physics, September 19, 2023. http://dx.doi.org/10.1088/1361-6463/acfb1a.

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Abstract A natural biaxial van der Waals material α-MoO3 hosts the in-plane anisotropy as well as the ultra-low-loss polaritons, which holds the great potential in the applications of subwavelength focusing, planar nanooptics as well as the polarization converters. Here, we show that the simple α-MoO3 slab supports the giant spin shifts of the reflected wave for either the horizontal (H) or vertical (V) polarized incident wave at the specific frequencies and the low as well as large incident angle regions, whose maximum values can reach their theoretical upper limit. Such the obtained giant spin shifts at the low and large incident angles are governed by the intrinsically in-plane anisotropy of α-MoO3 and the zero values of the reflectance at the transverse magnetic or electric wave. In addition, we also examine how the orientation of the optical axis of α-MoO3 slab controls the sign and magnitude of the reflected spin shifts and find that the positions where the maximum spin shifts of the reflected wave happen can be switched by rotating it. Our results on the reflected spin shifts in the α-MoO3 slab lay a foundation for unraveling the photonic spin Hall effects of anisotropic van der Waals crystals.

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Luo, Li, Xiao Liu, Shouxin Duan, Hui Li, Hang Xu, Sui Peng, Bo Liu, et al. "Dual channel transformation of scalar and vector terahertz beams along the optical path based on dielectric metasurface." Nanophotonics, September 22, 2023. http://dx.doi.org/10.1515/nanoph-2023-0457.

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Abstract The research on terahertz wave manipulation based on metasurfaces has gradually deepened, and the number of functions or electromagnetic control dimensions in a single device is constantly increasing. For the spatial dimension of terahertz field regulation, its design degrees of freedom have been expanded from a single transverse plane to the propagation path. In this paper, we propose a novel circularly polarization multiplexed metasurface for dual channel terahertz wave transmission control. Based on the spatial integration of two heterogeneous meta-atoms, which are spin-decoupled and isotropic, respectively, there are four phase channels that can be used at the same time, thus achieving different switching between vector and scalar beams in different circularly polarization channels along the optical path. For linearly polarized wave incidence, the device exhibits conversion between different vector beams longitudinally. To control more electric field components, we combine focused wavefront design with vector or scalar fields and utilize the focusing induced spin–orbit coupling effect, then complex amplitude switching of longitudinal electric field components is obtained. This article extends the manipulation of terahertz waves along the propagation trajectory based on metasurface from single to dual channel for the first time, providing a reference for the design of multifunctional meta-device in terahertz band.

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Yu, Feilong, Jin Chen, Lujun Huang, Zengyue Zhao, Jiuxu Wang, Rong Jin, Jian Chen, et al. "Photonic slide rule with metasurfaces." Light: Science & Applications 11, no. 1 (March 29, 2022). http://dx.doi.org/10.1038/s41377-022-00765-0.

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AbstractAs an elementary particle, a photon that carries information in frequency, polarization, phase, and amplitude, plays a crucial role in modern science and technology. However, how to retrieve the full information of unknown photons in an ultracompact manner over broad bandwidth remains a challenging task with growing importance. Here, we demonstrate a versatile photonic slide rule based on an all-silicon metasurface that enables us to reconstruct incident photons’ frequency and polarization state. The underlying mechanism relies on the coherent interactions of frequency-driven phase diagrams which rotate at various angular velocities within broad bandwidth. The rotation direction and speed are determined by the topological charge and phase dispersion. Specifically, our metasurface leverages both achromatically focusing and azimuthally evolving phases with topological charges +1 and −1 to ensure the confocal annular intensity distributions. The combination of geometric phase and interference holography allows the joint manipulations of two distinct group delay coverages to realize angle-resolved in-pair spots in a transverse manner- a behavior that would disperse along longitudinal direction in conventional implementations. The spin-orbital coupling between the incident photons and vortex phases provides routing for the simultaneous identification of the photons’ frequency and circular polarization state through recognizing the spots’ locations. Our work provides an analog of the conventional slide rule to flexibly characterize the photons in an ultracompact and multifunctional way and may find applications in integrated optical circuits or pocketable devices.

Journal articles on the topic 'Transverse magneto focusing'

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