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Journal articles on the topic 'Photon limited'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

De Leonardis, Francesco, Richard Soref, Martino De Carlo, and Vittorio M. N. Passaro. "On-Chip Group-IV Heisenberg-Limited Sagnac Interferometric Gyroscope at Room Temperature." Sensors 20, no. 12 (June 19, 2020): 3476. http://dx.doi.org/10.3390/s20123476.

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A room-temperature strip-guided “manufacturable” Silicon-on-Insulator (SOI)/GeSn integrated-photonics quantum-gyroscope chip operating at 1550 nm is proposed and analysed. We demonstrate how the entangled photons generated in Si Spontaneous Four Wave Mixing (SFWM) can be used to improve the resolution of a Sagnac interferometric gyroscope. We propose different integrated architectures based on degenerate and non-degenerate SFWM. The chip comprises several beam splitters, two SFWM entangled photon sources, a pump filter, integrated Mach–Zehnder interferometric gyro, and an array of waveguide coupled GeSn/Ge/Si single-photon avalanche detectors. The laser pumped SWFM sources generate the signal-idler pairs, which, in turn, are used to measure the two-photon, four-photon, and higher order coincidences, resulting in an increasing of the gyro resolution by a factor of two and four, with respect to the classical approach.

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2

Liu, Xialin, Jianhong Shi, Lei Sun, Yonghao Li, Jianping Fan, and Guihua Zeng. "Photon-limited single-pixel imaging." Optics Express 28, no. 6 (March 5, 2020): 8132. http://dx.doi.org/10.1364/oe.381785.

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3

Liu, Shaoxing, Xuanying Lai, Ce Yang, and J. F. Chen. "Towards High-Dimensional Entanglement in Path: Photon-Source Produced from a Two-Dimensional Atomic Cloud." Chinese Physics Letters 38, no. 8 (September 1, 2021): 084201. http://dx.doi.org/10.1088/0256-307x/38/8/084201.

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A photon source with high-dimensional entanglement is able to bring increasing capacity of information in quantum communication. The dimensionality is determined by the chosen degree of freedom of the photons and is limited by the complexity of the physical systems. Here we propose a new type of high-dimensional entangled photon source, generated via path-indistinguishable scheme from a two-dimensional atomic cloud, which is prepared in a magneto-optical trap. To verify the photon source, we demonstrate experimentally the quantum state of the single photons heralded by its partner photon, with homodyne tomographic technology.

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4

Tian, Qi Chuan, and Jie Wen. "Detecting Known Objects in a Noisy Scene Using Generalized Likelihood Ratio Test." Advanced Materials Research 518-523 (May 2012): 3843–46. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.3843.

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According to the problem of the identification and localization of a known object in a scene, satisfied detection results can not be achieved using traditional detectors for images in photon-limited noise, an algorithm named Generalized Likelihood Ratio Test (GLRT) was derived for detecting known objects in a noisy scene. We used this algorithm to evaluate the existence of tiger in photons-limited images. Results show that the GLRT algorithm is effectiveness in detecting and localizing a known object embedded in a background image from photon-limited observations.

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5

Schulz, Timothy J., David J. Brady, and Chengyu Wang. "Photon-limited bounds for phase retrieval." Optics Express 29, no. 11 (May 14, 2021): 16736. http://dx.doi.org/10.1364/oe.425796.

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6

Krishnamurthy, Kalyani, Maxim Raginsky, and Rebecca Willett. "Multiscale Photon-Limited Spectral Image Reconstruction." SIAM Journal on Imaging Sciences 3, no. 3 (January 2010): 619–45. http://dx.doi.org/10.1137/090756259.

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7

Piston, David W. "Two-Photon Excitation Microscopy in Cellular Biophysics." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 276–77. http://dx.doi.org/10.1017/s0424820100163848.

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Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10 5 limits the average input power to less than 10 mW, only slightly greater than the power normally used in confocal microscopy.Three properties TPEM give this method a tremendous advantage over conventional optical sectioning microscopies for the study of thick samples: 1) The excitation is limited to the focal volume because of the intensity-squared dependence of the two-photon absorption. This inherent localization provides three-dimensional resolution and eliminates background equivalent to an ideal confocal microscope without requiring a confocal spatial filter, whose absence enhances fluorescence collection efficiency. Confinement of excitation to the focal volume also minimizes photobleaching and photo damage - the ultimate limiting factors in fluorescence microscopy of living cells and tissues. 2) The two-photon technique allows imaging of UV fluorophores with conventional visible light optics in both the scanning and imaging systems, because both the red excitation light (~700 nm) and the blue fluorescence (>400 nm) are within the visible spectrum. 3) Red or infrared light is far less damaging to most living cells and tissues than bluer light because fewer biological molecules absorb at the higher wavelengths. Longer wavelength excitation also reduces scattering of the incident light by the specimen, thus allowing more of the input power to reach the focal plane. This relative transparency of biological specimens to 700 nm light permits deeper sectioning, since both absorbance and scattering are reduced.

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8

Nagy, Marius, and Naya Nagy. "Intrusion Detection Quantum Sensor Networks." Sensors 22, no. 21 (October 22, 2022): 8092. http://dx.doi.org/10.3390/s22218092.

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This paper proposes a perimeter detection scheme based on the quantum physical properties of photons. Existing perimeter intrusion detection schemes, if using light, rely on the classical properties of light only. Our quantum sensor network uses the quantum property of spatial superposition of photons, meaning that a photon can simultaneously follow two different paths after going through a beam splitter. Using multiple Mach–Zehnder interferometers, an entire web of paths can be generated, such that one single photon occupies them all. If an intruder violates this web in some arbitrary point, the entire photon superposition is destroyed, the photon does not self-interfere any more and this event is detected by measurements. For one single photon, the intruder detection probability is limited theoretically but can be increased arbitrarily with the usage of a sequence of photons. We show both theoretical bounds as well as practical results of the proposed schemes. The practical results are obtained by simulation experiments on IBM Quantum platforms. The benefits of our quantum approach are: low power, invisibility to potential intruders, scalability and easy practical implementation.

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9

Müller, J. Gerhard. "Photon Detection as a Process of Information Gain." Entropy 22, no. 4 (March 30, 2020): 392. http://dx.doi.org/10.3390/e22040392.

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Making use of the equivalence between information and entropy, we have shown in a recent paper that particles moving with a kinetic energy ε carry potential information i p o t ( ε , T ) = 1 ln ( 2 ) ε k B T relative to a heat reservoir of temperature T . In this paper we build on this result and consider in more detail the process of information gain in photon detection. Considering photons of energy E p h and a photo-ionization detector operated at a temperature T D , we evaluate the signal-to-noise ratio S N ( E p h , T D ) for different detector designs and detector operation conditions and show that the information gain realized upon detection, i r e a l ( E p h , T D ) , always remains smaller than the potential information i p o t ( E p h , T D ) carried with the photons themselves, i.e.,: i r e a l ( E p h , T D ) = 1 ln ( 2 ) ln ( S N ( E p h , T D ) ) ≤ i p o t ( E p h , T D ) = 1 ln ( 2 ) E p h k B T D . This result is shown to be generally valid for all kinds of technical photon detectors, which shows that i p o t ( E p h , T D ) can indeed be regarded as an intrinsic information content that is carried with the photons themselves. Overall, our results suggest that photon detectors perform as thermodynamic engines that incompletely convert potential information into realized information with an efficiency that is limited by the second law of thermodynamics and the Landauer energy bounds on information gain and information erasure.

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10

Frieden, B. Roy. "Maximum-probable restoration of photon-limited images." Applied Optics 26, no. 9 (May 1, 1987): 1755. http://dx.doi.org/10.1364/ao.26.001755.

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11

Mauskopf, P. D., S. Doyle, P. Barry, S. Rowe, A. Bidead, P. A. R. Ade, C. Tucker, et al. "Photon-Noise Limited Performance in Aluminum LEKIDs." Journal of Low Temperature Physics 176, no. 3-4 (January 14, 2014): 545–52. http://dx.doi.org/10.1007/s10909-013-1069-1.

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12

Park, Hyeon Jin, Chang Wook Song, Sourav Sarkar, Yong Woong Jun, Ye Jin Reo, Mingchong Dai, and Kyo Han Ahn. "A caveat to common hemicyanine dye components and their resolution." Chemical Communications 56, no. 51 (2020): 7025–28. http://dx.doi.org/10.1039/d0cc01833c.

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Hemicyanine dyes containing typical heterocycles such as 2-indolinium have limited chemo- and photo-stability issues, which can be resolved with a 4-pyridinium derivative that also shows good two-photon imaging capability.

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13

Giustolisi, Gianluca, Paolo Finocchiaro, Alfio Pappalardo, and Gaetano Palumbo. "Behavioral Model of Silicon Photo-Multipliers Suitable for Transistor-Level Circuit Simulation." Electronics 10, no. 13 (June 27, 2021): 1551. http://dx.doi.org/10.3390/electronics10131551.

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Silicon Photomultipliers (SiPMs) are photo-electronic devices able to detect single photons and permit the measurement of weak optical signals. Single-photon detection is accomplished through high-performance read-out front-end electronics whose design needs accurate modeling of the photomultiplier device. In the past, a useful model was developed, but it is limited to the device electrical characteristic and its parameter extraction procedure requires several measurement steps. A new silicon photomultiplier model is proposed in this paper. It exploits the Verilog-a behavioral language and is appropriate to transistor-level circuit simulations. The photon detection of a single cell is modeled using the traditional electrical model. A statistical model is included to describe the silicon photomultiplier noise caused by dark-count or after-pulsing effects. The paper also includes a procedure for the extraction of the model parameters through measurements. The Verilog-a model and the extraction procedure are validated by comparing simulations to experimental results.

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14

Piston, David W., Brian D. Bennett, and Robert G. Summers. "Two-photon excitation microscopy in cellular biophysics." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 62–63. http://dx.doi.org/10.1017/s0424820100136684.

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Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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15

Owen, James E., and Marcelo A. Alvarez. "UV DRIVEN EVAPORATION OF CLOSE-IN PLANETS: ENERGY-LIMITED, RECOMBINATION-LIMITED, AND PHOTON-LIMITED FLOWS." Astrophysical Journal 816, no. 1 (December 29, 2015): 34. http://dx.doi.org/10.3847/0004-637x/816/1/34.

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16

Khairulin, Ilias R., Yevgeny V. Radeonychev, and Olga Kocharovskaya. "Compression of the Synchrotron Mössbauer X-ray Photon Waveform in an Oscillating Resonant Absorber." Photonics 9, no. 11 (November 4, 2022): 829. http://dx.doi.org/10.3390/photonics9110829.

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A technique to transform the waveform of a 14.4 keV photon (time dependence of the photon detection probability or, equivalently, the intensity of the single-photon wave packet) into a regular sequence of short, nearly bandwidth-limited pulses with a controlled number of pulses is proposed. It is based on coherent forward scattering of single X-ray photons from a synchrotron Mössbauer source (SMS) in an optically thick, vibrating, recoilless 57Fe resonant absorber. The possibility of compressing the waveform of an SMS photon into a single short bell-shaped pulse is predicted. The experiment is proposed for compressing a 100 ns duration 14.4 keV single-photon wave packet produced by SMS at the European Synchrotron Radiation Facility (ESRF) into a single bell-shaped pulse of less than 20 ns duration and more than twice the peak intensity. Such single-photon coherent pulses are promising for applications in the fast-developing field of X-ray quantum optics, including possible implementation of quantum memory.

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17

Lee, Eldred, Kaitlin M. Anagnost, Zhehui Wang, Michael R. James, Eric R. Fossum, and Jifeng Liu. "Monte Carlo Modeling and Design of Photon Energy Attenuation Layers for >10× Quantum Yield Enhancement in Si-Based Hard X-ray Detectors." Instruments 5, no. 2 (April 30, 2021): 17. http://dx.doi.org/10.3390/instruments5020017.

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High-energy (>20 keV) X-ray photon detection at high quantum yield, high spatial resolution, and short response time has long been an important area of study in physics. Scintillation is a prevalent method but limited in various ways. Directly detecting high-energy X-ray photons has been a challenge to this day, mainly due to low photon-to-photoelectron conversion efficiencies. Commercially available state-of-the-art Si direct detection products such as the Si charge-coupled device (CCD) are inefficient for >10 keV photons. Here, we present Monte Carlo simulation results and analyses to introduce a highly effective yet simple high-energy X-ray detection concept with significantly enhanced photon-to-electron conversion efficiencies composed of two layers: a top high-Z photon energy attenuation layer (PAL) and a bottom Si detector. We use the principle of photon energy down conversion, where high-energy X-ray photon energies are attenuated down to ≤10 keV via inelastic scattering suitable for efficient photoelectric absorption by Si. Our Monte Carlo simulation results demonstrate that a 10–30× increase in quantum yield can be achieved using PbTe PAL on Si, potentially advancing high-resolution, high-efficiency X-ray detection using PAL-enhanced Si CMOS image sensors.

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18

Satherley, B., J. Oakley, C. Harrison, and C. Xydeas. "Simulation of photon-limited images using video data." Electronics Letters 32, no. 6 (1996): 535. http://dx.doi.org/10.1049/el:19960391.

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19

Abu-Naser, Ahmad, Nikolas P. Galatsanos, and Miles N. Wernick. "Methods to detect objects in photon-limited images." Journal of the Optical Society of America A 23, no. 2 (February 1, 2006): 272. http://dx.doi.org/10.1364/josaa.23.000272.

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20

Frenkel, A., M. A. Sartor, and M. S. Wlodawski. "Photon-noise-limited operation of intensified CCD cameras." Applied Optics 36, no. 22 (August 1, 1997): 5288. http://dx.doi.org/10.1364/ao.36.005288.

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21

He, Fang, Rui Liu, and Xin Tian. "Scanning-based photon-limited imaging through scattering media." Optics and Lasers in Engineering 161 (February 2023): 107388. http://dx.doi.org/10.1016/j.optlaseng.2022.107388.

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22

Piston, David W., Brian D. Bennett, and Guangtao Ying. "Imaging of Cellular Dynamics by Two-Photon Excitation Microscopy." Microscopy and Microanalysis 1, no. 1 (February 1995): 25–34. http://dx.doi.org/10.1017/s1431927695110259.

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Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons (∼700 nm) can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet (∼350 nm). In the fluorescence experiments described here, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g., wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. Three properties of two-photon excitation give this method its advantage over conventional optical sectioning microscopies: (1) the excitation is limited to the focal volume, thus providing inherent three-dimensional resolution and minimizing photobleaching and photodamage; (2) the two-photon technique allows imaging of UV fluorophores with only conventional visible light optics; (3) red light is far less damaging to most living cells and tissues than UV light and permits deeper sectioning, because both absorbance and scattering are reduced. Many cell biological applications of two-photon excitation microscopy have been successfully realized, demonstrating the wide ranging power of this technique.

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23

Saá Hernández, Ángela, Diego González-Díaz, Pablo Villanueva, Carlos Azevedo, and Marcos Seoane. "A new imaging technology based on Compton X-ray scattering." Journal of Synchrotron Radiation 28, no. 5 (July 22, 2021): 1558–72. http://dx.doi.org/10.1107/s1600577521005919.

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A feasible implementation of a novel X-ray detector for highly energetic X-ray photons with a large solid angle coverage, optimal for the detection of Compton X-ray scattered photons, is described. The device consists of a 20 cm-thick sensitive volume filled with xenon at atmospheric pressure. When the Compton-scattered photons interact with the xenon, the released photoelectrons create clouds of secondary ionization, which are imaged using the electroluminescence produced in a custom-made multi-hole acrylic structure. Photon-by-photon counting can be achieved by processing the resulting image, taken in a continuous readout mode. Based on Geant4 simulations, by considering a realistic detector design and response, it is shown that photon rates up to at least 1011 photons s−1 on-sample (5 µm water-equivalent cell) can be processed, limited by the spatial diffusion of the photoelectrons in the gas. Illustratively, if making use of the Rose criterion and assuming the dose partitioning theorem, it is shown how such a detector would allow obtaining 3D images of 5 µm-size unstained cells in their native environment in about 24 h, with a resolution of 36 nm.

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24

Zhang, Chen, and Kevin Welsher. "Information-Efficient, Off-Center Sampling Results in Improved Precision in 3D Single-Particle Tracking Microscopy." Entropy 23, no. 5 (April 22, 2021): 498. http://dx.doi.org/10.3390/e23050498.

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In this work, we present a 3D single-particle tracking system that can apply tailored sampling patterns to selectively extract photons that yield the most information for particle localization. We demonstrate that off-center sampling at locations predicted by Fisher information utilizes photons most efficiently. When performing localization in a single dimension, optimized off-center sampling patterns gave doubled precision compared to uniform sampling. A ~20% increase in precision compared to uniform sampling can be achieved when a similar off-center pattern is used in 3D localization. Here, we systematically investigated the photon efficiency of different emission patterns in a diffraction-limited system and achieved higher precision than uniform sampling. The ability to maximize information from the limited number of photons demonstrated here is critical for particle tracking applications in biological samples, where photons may be limited.

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25

Di Mitri, Simone. "One way only to synchrotron light sources upgrade?" Journal of Synchrotron Radiation 25, no. 5 (August 14, 2018): 1323–34. http://dx.doi.org/10.1107/s160057751800810x.

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The last decade has seen a renaissance of machine-physics studies and technological advancements that aim to upgrade at least 15 synchrotron light sources worldwide to diffraction-limited storage rings. This is expected to improve the average spectral brightness and transversally coherent fraction of photons by several orders of magnitude in the soft- and hard-X-ray wavelength range, at the expense of pulse durations longer than ∼80 ps FWHM. This paper discusses the compatibility of schemes for the generation of sub-picosecond photon-pulse durations in synchrotron light sources with standard multi-bunch user operation and, in particular, diffraction-limited electron optics design. The question of this compatibility is answered taking into consideration the storage ring beam energy and the constraint of existing synchrotrons' infrastructure. An alternative scheme for the upgrade of medium-energy synchrotron light sources to diffraction-limited storage rings and the simultaneous production of picosecond-long photon pulses in a high-gain free-electron laser scheme are illustrated.

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26

Piston, David W., James H. Strickler, and Watt W. Webb. "Application of two-photon chromophore excitation to laser scanning microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 404–5. http://dx.doi.org/10.1017/s0424820100086325.

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The non-linear optical technique of two-photon excitation of fluorescence and photochemical reactions makes possible new applications that are not possible using linear one-photon excitation in laser scanning confocal microscopy. The two-photon excitation effect arises from the simultaneous absorption of two red photons, which causes the transition to an excited electronic state with its normal absorption in the ultraviolet. In our fluorescence experiments, this excited state is the same singlet state, S1, that is populated during a conventional fluorescence experiment, and thus exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) that are observed in typical biological microscopy studies. Likewise, photochemical reactions such as light induced polymerization and photolytic uncaging that are normally catalyzed by UV light can be generated using two-photon excitation. In practice, twophoton excitation is made possible by the very high local instantaneous intensity that is provided by a combination of the diffraction limited focusing in the microscope and the temporal concentration of a subpicosecond mode-locked laser.

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27

Piston, David W. "Two-photon excitation fluorescence microscopy in living systems." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 154–55. http://dx.doi.org/10.1017/s0424820100146618.

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Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In our fluorescence experiments, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

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28

Li, Bin, Guangpeng Fan, Tianzhong Zhao, Zhuo Deng, and Yonghui Yu. "Retrieval of DTM under Complex Forest Stand Based on Spaceborne LiDAR Fusion Photon Correction." Remote Sensing 14, no. 1 (January 4, 2022): 218. http://dx.doi.org/10.3390/rs14010218.

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The new generation of satellite-borne laser radar Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) data has been successfully used for ground information acquisition. However, when dealing with complex terrain and dense vegetation cover, the accuracy of the extracted understory Digital Terrain Model (DTM) is limited. Therefore, this paper proposes a photon correction data processing method based on ICESat-2 to improve the DTM inversion accuracy in complex terrain and high forest coverage areas. The correction value is first extracted based on the ALOS PALSAR DEM reference data to correct the cross-track photon data of ICESat-2. The slope filter threshold is then selected from the reference data, and the extracted possible ground photons are slope filtered to obtain accurate ground photons. Finally, the impacts of cross-track photon and slope filtering on fine ground extraction from the ICESat-2 data are discussed. The results show that the proposed photon correction and slope filtering algorithms help to improve the extraction accuracy of forest DTM in complex terrain areas. Compared with the forest DTM extracted without the photon correction and slope filtering methods, the MAE (Mean Absolute Error) and RMSE (Root Mean Square Error) are reduced by 51.90~57.82% and 49.37~53.55%, respectively. To the best of our knowledge, this is the first study demonstrating that photon correction can improve the terrain inversion ability of ICESat-2, while providing a novel method for ground extraction based on ICESat-2 data. It provides a theoretical basis for the accurate inversion of canopy parameters for ICESat-2.

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29

Eiring, Patrick, Ryan McLaughlin, Siddharth S. Matikonda, Zhongying Han, Lennart Grabenhorst, Dominic A. Helmerich, Mara Meub, et al. "Targetable Conformationally Restricted Cyanines Enable Photon‐Count‐Limited Applications**." Angewandte Chemie 133, no. 51 (November 17, 2021): 26889–97. http://dx.doi.org/10.1002/ange.202109749.

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30

Eiring, Patrick, Ryan McLaughlin, Siddharth S. Matikonda, Zhongying Han, Lennart Grabenhorst, Dominic A. Helmerich, Mara Meub, et al. "Targetable Conformationally Restricted Cyanines Enable Photon‐Count‐Limited Applications**." Angewandte Chemie International Edition 60, no. 51 (November 17, 2021): 26685–93. http://dx.doi.org/10.1002/anie.202109749.

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31

Tang, J., J. Akerboom, A. Vaziri, L. L. Looger, and C. V. Shank. "Near-isotropic 3D optical nanoscopy with photon-limited chromophores." Proceedings of the National Academy of Sciences 107, no. 22 (May 14, 2010): 10068–73. http://dx.doi.org/10.1073/pnas.1004899107.

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32

Markman, Adam, and Bahram Javidi. "Integrated circuit authentication using photon-limited x-ray microscopy." Optics Letters 41, no. 14 (July 14, 2016): 3297. http://dx.doi.org/10.1364/ol.41.003297.

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33

Aitken, George J. M., and Robert Johnson. "Phase-gradient reconstruction from photon-limited stellar speckle images." Applied Optics 26, no. 19 (October 1, 1987): 4246. http://dx.doi.org/10.1364/ao.26.004246.

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34

Bashir, Muhammad Salman, and Sajid Sheikh Muhammad. "Time Synchronization in Photon-Limited Deep Space Optical Communications." IEEE Transactions on Aerospace and Electronic Systems 56, no. 1 (February 2020): 30–40. http://dx.doi.org/10.1109/taes.2019.2928667.

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35

Saaf, Lennart A., and G. Michael Morris. "Photon-limited image classification with a feedforward neural network." Applied Optics 34, no. 20 (July 10, 1995): 3963. http://dx.doi.org/10.1364/ao.34.003963.

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36

Yan, Kang, Li Lifei, Duan Xuejie, Zhang Tongyi, Li Dongjian, and Zhao Wei. "Photon-limited depth and reflectivity imaging with sparsity regularization." Optics Communications 392 (June 2017): 25–30. http://dx.doi.org/10.1016/j.optcom.2017.01.032.

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37

Watson, Edward A., and G. Michael Morris. "Comparison of infrared upconversion methods for photon‐limited imaging." Journal of Applied Physics 67, no. 10 (May 15, 1990): 6075–84. http://dx.doi.org/10.1063/1.345167.

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38

Nikitin, Viktor, Selin Aslan, Yudong Yao, Tekin Biçer, Sven Leyffer, Rajmund Mokso, and Doğa Gürsoy. "Photon-limited ptychography of 3D objects via Bayesian reconstruction." OSA Continuum 2, no. 10 (October 8, 2019): 2948. http://dx.doi.org/10.1364/osac.2.002948.

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39

Lucke, Robert L., and Lee J. Rickard. "Photon-limited synthetic-aperture imaging for planet surface studies." Applied Optics 41, no. 24 (August 20, 2002): 5084. http://dx.doi.org/10.1364/ao.41.005084.

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40

Sanghvi, Yash, Abhiram Gnanasambandam, Zhiyuan Mao, and Stanley H. Chan. "Photon-Limited Blind Deconvolution Using Unsupervised Iterative Kernel Estimation." IEEE Transactions on Computational Imaging 8 (2022): 1051–62. http://dx.doi.org/10.1109/tci.2022.3226947.

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41

Huang, Hong-Mei, and Lu-Ping Xu. "Design and Analysis of the Secure Scheme for Quantum Positioning based on Entangled Photon Pair." International Journal of Technology and Human Interaction 12, no. 2 (April 2016): 22–35. http://dx.doi.org/10.4018/ijthi.2016040102.

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Positioning accuracy of the traditional positioning has been limited because of the power and bandwidth limitation, quantum entanglement and compression technology can greatly improve the accuracy of measurement and synchronization. So, using the coherence of entangled photons and the principle of quantum spatial positioning, the scheme of quantum positioning with entangled photon pair was proposed, which was consisted of ground unit, satellite and the user three parts, the ground unit respectively sent EPR entangled photon pairs to two satellites three times, then the entangled photon pairs were sent to user by satellites, User carrying HOM interferometer, when the coincidence counting rate reaches the maximum three times, the user location can be got by computing. In the end, the quantum positioning and the traditional positioning technology were compared from the aspects of positioning accuracy, safety and so on.

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McLaughlin, Joseph Biagio, Giacomo Gallina, Fabrice Retière, Austin De St. Croix, Pietro Giampa, Mahsa Mahtab, Peter Margetak, et al. "Characterisation of SiPM Photon Emission in the Dark." Sensors 21, no. 17 (September 4, 2021): 5947. http://dx.doi.org/10.3390/s21175947.

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In this paper, we report on the photon emission of Silicon Photomultipliers (SiPMs) from avalanche pulses generated in dark conditions, with the main objective of better understanding the associated systematics for next-generation, large area, SiPM-based physics experiments. A new apparatus for spectral and imaging analysis was developed at TRIUMF and used to measure the light emitted by the two SiPMs considered as photo-sensor candidates for the nEXO neutrinoless double-beta decay experiment: one Fondazione Bruno Kessler (FBK) VUV-HD Low Field (LF) Low After Pulse (Low AP) (VUV-HD3) SiPM and one Hamamatsu Photonics K.K. (HPK) VUV4 Multi-Pixel Photon Counter (MPPC). Spectral measurements of their light emissions were taken with varying over-voltage in the wavelength range of 450–1020 nm. For the FBK VUV-HD3, at an over-voltage of 12.1±1.0 V, we measured a secondary photon yield (number of photons (γ) emitted per charge carrier (e−)) of (4.04±0.02)×10−6γ/e−. The emission spectrum of the FBK VUV-HD3 contains an interference pattern consistent with thin-film interference. Additionally, emission microscopy images (EMMIs) of the FBK VUV-HD3 show a small number of highly localized regions with increased light intensity (hotspots) randomly distributed over the SiPM surface area. For the HPK VUV4 MPPC, at an over-voltage of 10.7±1.0 V, we measured a secondary photon yield of (8.71±0.04)×10−6γ/e−. In contrast to the FBK VUV-HD3, the emission spectra of the HPK VUV4 did not show an interference pattern—likely due to a thinner surface coating. The EMMIs of the HPK VUV4 also revealed a larger number of hotspots compared to the FBK VUV-HD3, especially in one of the corners of the device. The photon yield reported in this paper may be limited if compared with the one reported in previous studies due to the measurement wavelength range, which is only up to 1020 nm.

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43

Wu, Thakur, Chiang, Chandel, Wang, Chiu, and Chang. "The Way to Pursue Truly High-Performance Perovskite Solar Cells." Nanomaterials 9, no. 9 (September 5, 2019): 1269. http://dx.doi.org/10.3390/nano9091269.

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The power conversion efficiency (PCE) of single-junction solar cells was theoretically predicted to be limited by the Shockley–Queisser limit due to the intrinsic potential loss of the photo-excited electrons in the light absorbing materials. Up to now, the optimized GaAs solar cell has the highest PCE of 29.1%, which is close to the theoretical limit of ~33%. To pursue the perfect photovoltaic performance, it is necessary to extend the lifetimes of the photo-excited carriers (hot electrons and hot holes) and to collect the hot carriers without potential loss. Thanks to the long-lived hot carriers in perovskite crystal materials, it is possible to completely convert the photon energy to electrical power when the hot electrons and hot holes can freely transport in the quantized energy levels of the electron transport layer and hole transport layer, respectively. In order to achieve the ideal PCE, the interactions between photo-excited carriers and phonons in perovskite solar cells has to be completely understood.

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44

König, Karsten. "Two-Photon near Infrared Excitation in Living Cells." Journal of Near Infrared Spectroscopy 5, no. 1 (January 1997): 27–34. http://dx.doi.org/10.1255/jnirs.97.

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Non-linear effects due to two-photon near infrared (NIR) excitation of endogenous and exogenous cellular chromophores allow novel techniques in tissue, cell and biomolecule diagnostics, as well as in intracellular micromanipulation (e.g. intracellular photochemistry). Two-photon NIR excitation may also result in cell damage effects. The high photon intensities (1024 photons cm−2 s−1) required for non-resonant two-photon excitation can be achieved by diffraction-limited focusing of continuous wave (cw) laser beams (cw microbeams) with powers in the mW range. For example, NIR traps (“laser tweezers”) used as force transducers and micromanipulation tools in cellular and molecular biology are sources of two-photon excitation. NIR traps can induce two-photon excited visible fluorescence and, in the case of <800 nm-traps, UVA-like cell damage. Multimode cw microbeams may enhance non-linear effects due to longitudinal mode-beating. To perform high scan rate two-photon fluorescence imaging, the application of ultrashort laser pulses of moderate peak power but low average power (pulsed microbeams) is required. In NIR femtosecond microscopes, non-destructive imaging of two-photon excited fluorophores in various human and culture cells was demonstrated for <2 mW average powers, <200 mW peak powers and 400 GW cm−2 intensities (700–800 nm, ∼150 fs, ∼100 MHz). However, higher average power levels may result in failed cell reproduction and cell death due to intracellular optical breakdown. In addition, destructive transient local heating and μN force generation may occur.

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Denk, Winfried. "Multi-Photon Microscopy, High Resolution Imaging Deep in Strongly Scattering Specimens." Microscopy and Microanalysis 3, S2 (August 1997): 301–2. http://dx.doi.org/10.1017/s1431927600008394.

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Imaging small structures substantially below the tissue surface in living specimens poses special challenges mainly because light is scattered by ever present refractive index inhomogeneities. Confocal microscoy removes the blurring caused by scattered and out-of-focus light but does so only at the expense of photodynamic damage that is often unacceptable when observing live specimens.Multi-photon absorption microscopy[l] solves these problems because excitation is virtually limited to the focal plane. Out-of-focus photobleaching and photodamage are therefore eliminated. In scattering samples substantial improvements accrue even for the focal plane because, different from confocal microscopy, where only ballistic fluorescenc photons can be used, in the multi-photon microscope scattered photons can be utilized in addition [2-4], provided whole-field detection is used[5].Many questions in the study of the nervous system require the investigation of intact portions of neural tissue in order to preserve the multiply branched processes of neurons, often extending over hundreds of microns, together with the local nervous circuitry.

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46

Wier, W. Gil, C. William Balke, Jeffrey A. Michael, and Joseph R. H. Mauban. "A custom confocal and two-photon digital laser scanning microscope." American Journal of Physiology-Heart and Circulatory Physiology 278, no. 6 (June 1, 2000): H2150—H2156. http://dx.doi.org/10.1152/ajpheart.2000.278.6.h2150.

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We describe a custom one-photon (confocal) and two-photon all-digital (photon counting) laser scanning microscope. The confocal component uses two avalanche photodiodes (APDs) as the fluorescence detector to achieve high sensitivity and to overcome the limited photon counting rate of a single APD (∼5 MHz). The confocal component is approximately nine times more efficient than our commercial confocal microscope (fluorophore fluo 4). Switching from one-photon to two-photon excitation mode (Ti:sapphire laser) is accomplished by moving a single mirror beneath the objective lens. The pulse from the Ti:sapphire laser is 109 fs in duration at the specimen plane, and average power is ∼5 mW. Two-photon excited fluorescence is detected by a fast photomultiplier tube. With a ×63 1.4 NA oil-immersion objective, the resolution of the confocal system is 0.25 μm laterally and 0.52 μm axially. For the two-photon system, the corresponding values are 0.28 and 0.82 μm. The system is advantageous when excitation intensity must be limited, when fluorescence is low, or when thick, scattering specimens are being studied (with two-photon excitation).

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47

Dhere, Vishal Ramesh, Ashesh B. Jani, Benjamin Walker Fischer-Valuck, Sherrie Cooper, Joseph W. Shelton, Bruce Warren Hershatter, Subir Goyal, et al. "Impact of rectal spacer on toxicity reduction in men treated with proton versus photon therapy." Journal of Clinical Oncology 40, no. 6_suppl (February 20, 2022): 247. http://dx.doi.org/10.1200/jco.2022.40.6_suppl.247.

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247 Background: Dose escalation in prostate cancer (PCa) radiotherapy (RT) is limited by toxicity to surrounding tissue, including the rectum. Rectal spacers improve bowel toxicity in men treated with photons (i.e. IMRT). However, the relative benefit of rectal spacers in men treated with protons remains unknown. Further, proton therapy may result in high-dose exposure to the anterior rectal wall due to lateral penumbra with conventional opposed lateral beam arrangement. We hypothesize that rectal spacers will confer greater toxicity benefit in the setting of proton therapy compared with photon therapy. Methods: We conducted an IRB approved, single institution, retrospective review of patients receiving definitive conventional or moderate hypofractionated photon IMRT or pencil-beam scanning proton RT for localized PCa from 2018-2021. Four cohorts were compared: Photon with (Ph+RS) or without (Ph-RS) rectal spacer, and proton with (Pr+RS) or without (Pr-RS) rectal spacer. Rates of pelvic nodal treatment were equivalent between protons and photons within the +/- rectal spacer cohorts. Acute (<3 months) and late (≥ 3 month) toxicity was compared amongst the four cohorts. Cumulative incidence of physician-reported grade 1-2 gastrointestinal (GI) toxicity (CTCAE V5.0) was compared using Chi-square or Fisher’s exact test. Patient-reported bowel toxicity was evaluated using International Prostate Expanded Prostate Composite Index- Clinical Practice (EPIC-CP) and compared using linear mixed modeling. Results: 164 patients were eligible for analysis: 38 Ph-RS, 50 Ph+RS, 26 Pr-RS, & 50 Pr+RS. Median follow-up was 17.6 months. In men treated with protons, physician-reported acute G1-2 GI toxicity was significantly lower in men with versus without rectal spacer (6.12 vs 30.77%, Pr+RS vs Pr-RS, respectively; p=0.009) and there was a trend towards lower late G1-2 GI toxicity (8.51 vs 26.09%, Pr+RS vs Pr-RS, respectively; p=0.08). In men treated with photons, there were no significant differences in physician-reported acute or later GI toxicity with versus without rectal spacer. No significant differences in patient-reported outcomes were observed with versus without spacer in the proton or photon cohorts. Conclusions: Rectal spacer use was associated with a lower CTCAE grade 1-2 acute GI toxicity in men treated with protons, and this difference was not observed in men treated with photons. While this study is limited by low sample size, a relatively greater benefit of rectal spacer with proton vs. photon therapy was observed. Further prospective analyses in larger cohorts are ongoing to validate these hypothesis-generating findings.

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48

Czerwiński, Eryk, Catalina Curceanu, Kamil Dulski, Aleksander Gajos, Marek Gorgol, Andrzej Heczko, Beatrix C. Hiesmayr, et al. "Studies of discrete symmetries in decays of positronium atoms." EPJ Web of Conferences 181 (2018): 01019. http://dx.doi.org/10.1051/epjconf/201818101019.

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A positronium - a bound state of electron and positron - is an eigenstate of parity and charge conjugation operators which decays into photons. It is a unique laboratory to study discrete symmetries whose precision is limited, in principle, by the effects due to the weak interactions expected at the level of 10−14 and photon-photon interactions expected at the level of 10−9. The Jagiellonian Positron Emission Tomograph (J-PET) is a detector for medical imaging as well as for physics studies involving detection of electronpositron annihilation into photons. The physics case covers the areas of discrete symmetries studies and genuine multipartite entanglement. The J-PET detector has high angular and time resolution and allows for determination of spin of the positronium and the momenta and polarization vectors of annihilation quanta. In this article, we present the potential of the J-PET system for studies of discrete symmetries in decays of positronium atoms.

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Han, Jing, Jinye Miao, Yingjie Shi, Shuo Zhu, Yan Sun, Lianfa Bai, and Enlai Guo. "Photon-limited imaging through scattering medium based on speckle coding." Optik 255 (April 2022): 168643. http://dx.doi.org/10.1016/j.ijleo.2022.168643.

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50

White, John Thomas, and Subhashis Ghosal. "Bayesian smoothing of photon-limited images with applications in astronomy." Journal of the Royal Statistical Society: Series B (Statistical Methodology) 73, no. 4 (July 1, 2011): 579–99. http://dx.doi.org/10.1111/j.1467-9868.2011.00776.x.

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