After decades of research, there are almost half a dozen efficiently pumped rare earth laser transitions in a fiber laser format capable of Watt-level output. These systems use near-IR laser diodes for excitation and have developed into reliable sources of high beam quality light with some commercially available. This maturation of the mid-IR fiber laser is entirely based on a high quality fluoride glass fiber, which has emerged as the primary fiber gain material for emission up to 4 µm. The other major mid-IR transparent glass families, the heavy metal oxides, and chalcogenides have always been challenged by consistent hydrogen diffusion into the glass that creates strong absorption features in the high-frequency portions of the mid-IR. This problem along with challenges to sufficiently concentrate the rare earth doping level has historically stifled progress preventing fiber laser emission in the mid-IR. In recent years, great efforts in precursor purification and reducing contamination during fabrication have resulted in pioneering demonstrations of mid-IR lasing using these glasses with emission now extending beyond 5 µm. As a result, mid-IR fiber laser research has entered a new era with more breakthroughs and applications to benefit from the efficiency potential, reliability, and relatively simple architecture of the optical fiber.
{"title":"Mid-infrared fiber laser research: Tasks completed and the tasks ahead","authors":"S. D. Jackson","doi":"10.1063/5.0220406","DOIUrl":"https://doi.org/10.1063/5.0220406","url":null,"abstract":"After decades of research, there are almost half a dozen efficiently pumped rare earth laser transitions in a fiber laser format capable of Watt-level output. These systems use near-IR laser diodes for excitation and have developed into reliable sources of high beam quality light with some commercially available. This maturation of the mid-IR fiber laser is entirely based on a high quality fluoride glass fiber, which has emerged as the primary fiber gain material for emission up to 4 µm. The other major mid-IR transparent glass families, the heavy metal oxides, and chalcogenides have always been challenged by consistent hydrogen diffusion into the glass that creates strong absorption features in the high-frequency portions of the mid-IR. This problem along with challenges to sufficiently concentrate the rare earth doping level has historically stifled progress preventing fiber laser emission in the mid-IR. In recent years, great efforts in precursor purification and reducing contamination during fabrication have resulted in pioneering demonstrations of mid-IR lasing using these glasses with emission now extending beyond 5 µm. As a result, mid-IR fiber laser research has entered a new era with more breakthroughs and applications to benefit from the efficiency potential, reliability, and relatively simple architecture of the optical fiber.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"62 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joshua C. Lederman, Simon Bilodeau, Eli Doris, Eric C. Blow, Weipeng Zhang, Yusuf Jimoh, Bhavin J. Shastri, Paul R. Prucnal
Analog photonic information processing can be implemented with low chip area using wavelength-division multiplexed systems, which typically manipulate light using micro-ring resonators. Micro-rings are uniquely susceptible to thermal crosstalk, with negative system performance consequences if not addressed. Existing thermal sensitivity mitigation methods face drawbacks including high complexity, high latency, high digital and analog hardware requirements, and CMOS incompatibility. Here, we demonstrate a passive thermal desensitization mechanism for silicon micro-ring resonators exploiting self-heating resulting from optical absorption. We achieve a 49% reduction in thermal crosstalk sensitivity and 1 µs adaptation latency using a system with no specialized micro-ring engineering, no additional control hardware, and no additional calibration. Our theoretical model indicates the potential for significant further desensitization gains with optimized micro-ring designs. Self-heating desensitization can be combined with active thermal stabilization to achieve both responsiveness and accuracy or applied independently to thermally desensitize large photonic systems for signal processing or neural network inference.
{"title":"Low-latency passive thermal desensitization of a silicon micro-ring resonator with self-heating","authors":"Joshua C. Lederman, Simon Bilodeau, Eli Doris, Eric C. Blow, Weipeng Zhang, Yusuf Jimoh, Bhavin J. Shastri, Paul R. Prucnal","doi":"10.1063/5.0212591","DOIUrl":"https://doi.org/10.1063/5.0212591","url":null,"abstract":"Analog photonic information processing can be implemented with low chip area using wavelength-division multiplexed systems, which typically manipulate light using micro-ring resonators. Micro-rings are uniquely susceptible to thermal crosstalk, with negative system performance consequences if not addressed. Existing thermal sensitivity mitigation methods face drawbacks including high complexity, high latency, high digital and analog hardware requirements, and CMOS incompatibility. Here, we demonstrate a passive thermal desensitization mechanism for silicon micro-ring resonators exploiting self-heating resulting from optical absorption. We achieve a 49% reduction in thermal crosstalk sensitivity and 1 µs adaptation latency using a system with no specialized micro-ring engineering, no additional control hardware, and no additional calibration. Our theoretical model indicates the potential for significant further desensitization gains with optimized micro-ring designs. Self-heating desensitization can be combined with active thermal stabilization to achieve both responsiveness and accuracy or applied independently to thermally desensitize large photonic systems for signal processing or neural network inference.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"24 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we establish the theoretical framework for understanding the sensing capabilities of megameter-long submarine optical cables. We show the distinct advantage of polarization over phase in detecting sub-hertz environmental processes. Subsequently, we propose a scheme capable of extracting the spectrum of perturbations affecting a specific section at any position along an optical fiber by detecting the state of polarization of the backreflected light. We discuss two examples of earthquake detection and the detection of sea swells and ocean tides through the analysis of the state of polarization of an optical signal reconstructed by the receiver of a transoceanic cable, obtained from an online database [Z. Zhan, “Curie Data - Zhan et al. (2021)” (2020)]. Finally, we provide the analytical expression for the cross correlation of the polarization perturbations of two wavelength division multiplexed channels and show that the analysis of the polarization correlations between adjacent channels can provide valuable insights into the localization of earthquakes.
{"title":"Sensing with submarine optical cables","authors":"Antonio Mecozzi","doi":"10.1063/5.0210825","DOIUrl":"https://doi.org/10.1063/5.0210825","url":null,"abstract":"In this paper, we establish the theoretical framework for understanding the sensing capabilities of megameter-long submarine optical cables. We show the distinct advantage of polarization over phase in detecting sub-hertz environmental processes. Subsequently, we propose a scheme capable of extracting the spectrum of perturbations affecting a specific section at any position along an optical fiber by detecting the state of polarization of the backreflected light. We discuss two examples of earthquake detection and the detection of sea swells and ocean tides through the analysis of the state of polarization of an optical signal reconstructed by the receiver of a transoceanic cable, obtained from an online database [Z. Zhan, “Curie Data - Zhan et al. (2021)” (2020)]. Finally, we provide the analytical expression for the cross correlation of the polarization perturbations of two wavelength division multiplexed channels and show that the analysis of the polarization correlations between adjacent channels can provide valuable insights into the localization of earthquakes.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"24 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frederik Thiele, Niklas Lamberty, Thomas Hummel, Tim Bartley
Cryogenic opto-electronic interconnects are gaining increasing interest as a means to control and readout cryogenic electronic components. The challenge is to achieve sufficient signal integrity with low heat load processing. In this context, we demonstrate the opto-electronic bias and readout of a commercial four-pixel superconducting nanowire single-photon detector array using a cryogenic photodiode and laser. We show that this approach has a similar system detection efficiency to a conventional bias. Furthermore, multi-pixel detection events are faithfully converted between the optical and electrical domains, which allows reliable extraction of amplitude multiplexed photon statistics. Our device has a latent heat load of 2.6 mW, maintains a signal rise time of 3 ns, and operates in free-running (self-resetting) mode at a repetition rate of 600 kHz. This demonstrates the potential of high-bandwidth, low noise, and low heat load opto-electronic interconnects for scalable cryogenic signal processing and transmission.
{"title":"Optical bias and cryogenic laser readout of a multipixel superconducting nanowire single photon detector","authors":"Frederik Thiele, Niklas Lamberty, Thomas Hummel, Tim Bartley","doi":"10.1063/5.0209458","DOIUrl":"https://doi.org/10.1063/5.0209458","url":null,"abstract":"Cryogenic opto-electronic interconnects are gaining increasing interest as a means to control and readout cryogenic electronic components. The challenge is to achieve sufficient signal integrity with low heat load processing. In this context, we demonstrate the opto-electronic bias and readout of a commercial four-pixel superconducting nanowire single-photon detector array using a cryogenic photodiode and laser. We show that this approach has a similar system detection efficiency to a conventional bias. Furthermore, multi-pixel detection events are faithfully converted between the optical and electrical domains, which allows reliable extraction of amplitude multiplexed photon statistics. Our device has a latent heat load of 2.6 mW, maintains a signal rise time of 3 ns, and operates in free-running (self-resetting) mode at a repetition rate of 600 kHz. This demonstrates the potential of high-bandwidth, low noise, and low heat load opto-electronic interconnects for scalable cryogenic signal processing and transmission.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"63 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rishyashring R. Iyer, Lingxiao Yang, Janet E. Sorrells, Eric J. Chaney, Darold R. Spillman, Stephen A. Boppart
The applications of ultrafast optics to biomedical microscopy have expanded rapidly in recent years, including interferometric techniques like optical coherence tomography and microscopy (OCT/OCM). The advances of ultra-high resolution OCT and the inclusion of OCT/OCM in multimodal systems combined with multiphoton microscopy have marked a transition from using pseudo-continuous broadband sources, such as superluminescent diodes, to ultrafast supercontinuum optical sources. We report anomalies in the dispersion profiles of low-coherence ultrafast pulses through long and non-identical arms of a Michelson interferometer that are well beyond group delay or third-order dispersions. This chromatic anomaly worsens the observed axial resolution and causes fringe artifacts in the reconstructed tomograms in OCT/OCM using traditional algorithms. We present DISpersion COmpensation Techniques for Evident Chromatic Anomalies (DISCOTECA) as a universal solution to address the problem of chromatic dispersion mismatch in interferometry, especially with ultrafast sources. First, we demonstrate the origin of these artifacts through the self-phase modulation of ultrafast pulses due to focusing elements in the beam path. Next, we present three solution paradigms for DISCOTECA: optical, optoelectronic, and computational, along with quantitative comparisons to traditional methods to highlight the improvements to the dynamic range and axial profile. We explain the piecewise reconstruction of the phase mismatch between the arms of the spectral-domain interferometer using a modified short-term Fourier transform algorithm inspired by spectroscopic OCT. Finally, we present a decision-making guide for evaluating the utility of DISCOTECA in interferometry and for the artifact-free reconstruction of OCT images using an ultrafast supercontinuum source for biomedical applications.
近年来，超快光学在生物医学显微镜方面的应用迅速扩大，其中包括光学相干断层扫描和显微镜（OCT/OCM）等干涉测量技术。超高分辨率 OCT 的发展以及将 OCT/OCM 纳入与多光子显微镜相结合的多模态系统，标志着从使用伪连续宽带光源（如超发光二极管）到超快超连续光学光源的过渡。我们报告了低相干超快脉冲在通过迈克尔逊干涉仪的非相同长臂时的色散曲线异常现象，这种异常现象远远超出了群延迟或三阶色散。这种色度异常会降低观察到的轴向分辨率，并在使用传统算法的 OCT/OCM 重建断层图中造成条纹伪影。我们提出了针对明显色度异常的色散补偿技术（DISCOTECA），作为解决干涉测量（尤其是超快光源）中色散失配问题的通用解决方案。首先，我们通过光束路径中的聚焦元件引起的超快脉冲自相位调制，证明了这些伪影的起源。接下来，我们介绍了 DISCOTECA 的三种解决范例：光学、光电和计算，并与传统方法进行了定量比较，以突出动态范围和轴向剖面的改进。我们解释了光谱域干涉仪两臂之间相位失配的分片重建，使用的是受光谱 OCT 启发而改进的短期傅立叶变换算法。最后，我们提出了一个决策指南，用于评估 DISCOTECA 在干涉测量中的实用性，以及在生物医学应用中使用超快超连续光源对 OCT 图像进行无伪影重建。
{"title":"Dispersion mismatch correction for evident chromatic anomaly in low coherence interferometry","authors":"Rishyashring R. Iyer, Lingxiao Yang, Janet E. Sorrells, Eric J. Chaney, Darold R. Spillman, Stephen A. Boppart","doi":"10.1063/5.0207414","DOIUrl":"https://doi.org/10.1063/5.0207414","url":null,"abstract":"The applications of ultrafast optics to biomedical microscopy have expanded rapidly in recent years, including interferometric techniques like optical coherence tomography and microscopy (OCT/OCM). The advances of ultra-high resolution OCT and the inclusion of OCT/OCM in multimodal systems combined with multiphoton microscopy have marked a transition from using pseudo-continuous broadband sources, such as superluminescent diodes, to ultrafast supercontinuum optical sources. We report anomalies in the dispersion profiles of low-coherence ultrafast pulses through long and non-identical arms of a Michelson interferometer that are well beyond group delay or third-order dispersions. This chromatic anomaly worsens the observed axial resolution and causes fringe artifacts in the reconstructed tomograms in OCT/OCM using traditional algorithms. We present DISpersion COmpensation Techniques for Evident Chromatic Anomalies (DISCOTECA) as a universal solution to address the problem of chromatic dispersion mismatch in interferometry, especially with ultrafast sources. First, we demonstrate the origin of these artifacts through the self-phase modulation of ultrafast pulses due to focusing elements in the beam path. Next, we present three solution paradigms for DISCOTECA: optical, optoelectronic, and computational, along with quantitative comparisons to traditional methods to highlight the improvements to the dynamic range and axial profile. We explain the piecewise reconstruction of the phase mismatch between the arms of the spectral-domain interferometer using a modified short-term Fourier transform algorithm inspired by spectroscopic OCT. Finally, we present a decision-making guide for evaluating the utility of DISCOTECA in interferometry and for the artifact-free reconstruction of OCT images using an ultrafast supercontinuum source for biomedical applications.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"2 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Optoelectronic oscillators (OEOs), which have attracted extensive studies in the past decades, are high quality-factor optoelectronic feedback loops for generating various ultra-pure microwave signals. In essence, OEOs are also dissipative nonlinear systems with multiple timescale characteristics and abundant nonlinearities, which open the possibilities for exploring localized dissipative solitary waves. In this paper, we demonstrate a new-class temporal dissipative soliton, i.e., dissipative microwave photonic soliton molecule (DMPSM), in a dual-bandpass OEO. Both the numerical simulation and experiment are conducted to reveal the physical mechanism of DMPSM generation and to evaluate the characteristics of the generated DMPSM sequences. Unlike optical soliton molecules in mode-locked lasers, the formation of DMPSMs arises from the combined action of multiple timescale coupling, nonlinear bistability, and time-delayed feedback in the OEO cavity, where the soliton interval and number in a DMPSM can be well-controlled through varying the multiple timescale variables in the OEO cavity, and the repetition frequency of the DMPSMs can be tuned through changing that of the initially injected perturbation signal. Meanwhile, the generated DMPSM sequence performs with high stability and excellent coherence, which shows enormous application potentials in pulse radar detection, dense microwave comb generation, and neuromorphology.
{"title":"Discovery of dissipative microwave photonic soliton molecules in dual-bandpass optoelectronic oscillator","authors":"Huan Tian, Junwen Li, Weiqiang Lyu, Lingjie Zhang, Zhen Zeng, Yaowen Zhang, Zhiyao Zhang, Shangjian Zhang, Heping Li, Yong Liu","doi":"10.1063/5.0205357","DOIUrl":"https://doi.org/10.1063/5.0205357","url":null,"abstract":"Optoelectronic oscillators (OEOs), which have attracted extensive studies in the past decades, are high quality-factor optoelectronic feedback loops for generating various ultra-pure microwave signals. In essence, OEOs are also dissipative nonlinear systems with multiple timescale characteristics and abundant nonlinearities, which open the possibilities for exploring localized dissipative solitary waves. In this paper, we demonstrate a new-class temporal dissipative soliton, i.e., dissipative microwave photonic soliton molecule (DMPSM), in a dual-bandpass OEO. Both the numerical simulation and experiment are conducted to reveal the physical mechanism of DMPSM generation and to evaluate the characteristics of the generated DMPSM sequences. Unlike optical soliton molecules in mode-locked lasers, the formation of DMPSMs arises from the combined action of multiple timescale coupling, nonlinear bistability, and time-delayed feedback in the OEO cavity, where the soliton interval and number in a DMPSM can be well-controlled through varying the multiple timescale variables in the OEO cavity, and the repetition frequency of the DMPSMs can be tuned through changing that of the initially injected perturbation signal. Meanwhile, the generated DMPSM sequence performs with high stability and excellent coherence, which shows enormous application potentials in pulse radar detection, dense microwave comb generation, and neuromorphology.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"41 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photonic neuromorphic computing has emerged as a promising avenue toward building a high-speed, low-latency, and energy-efficient non-von-Neumann computing system. Photonic spiking neural network (PSNN) exploits brain-like spatiotemporal processing to realize high-performance neuromorphic computing. Linear weighting and nonlinear spiking activation are two fundamental functions of a SNN. However, the nonlinear computation of PSNN remains a significant challenge. Therefore, this perspective focuses on the nonlinear computation of photonic spiking neurons, including numerical simulation, device fabrication, and experimental demonstration. Different photonic spiking neurons are considered, such as vertical-cavity surface-emitting lasers, distributed feedback (DFB) lasers, Fabry–Pérot (FP) lasers, or semiconductor lasers embedded with saturable absorbers (SAs) (e.g., FP-SA and DFB-SA). PSNN architectures, including fully connected and convolutional structures, are developed, and supervised and unsupervised learning algorithms that take into account optical constraints are introduced to accomplish specific applications. This work covers devices, architectures, learning algorithms, and applications for photonic and optoelectronic neuromorphic computing and provides our perspective on the challenges and prospects of photonic neuromorphic computing based on semiconductor lasers.
{"title":"Semiconductor lasers for photonic neuromorphic computing and photonic spiking neural networks: A perspective","authors":"Shuiying Xiang, Yanan Han, Shuang Gao, Ziwei Song, Yahui Zhang, Dianzhuang Zheng, Chengyang Yu, Xingxing Guo, XinTao Zeng, Zhiquan Huang, Yue Hao","doi":"10.1063/5.0217968","DOIUrl":"https://doi.org/10.1063/5.0217968","url":null,"abstract":"Photonic neuromorphic computing has emerged as a promising avenue toward building a high-speed, low-latency, and energy-efficient non-von-Neumann computing system. Photonic spiking neural network (PSNN) exploits brain-like spatiotemporal processing to realize high-performance neuromorphic computing. Linear weighting and nonlinear spiking activation are two fundamental functions of a SNN. However, the nonlinear computation of PSNN remains a significant challenge. Therefore, this perspective focuses on the nonlinear computation of photonic spiking neurons, including numerical simulation, device fabrication, and experimental demonstration. Different photonic spiking neurons are considered, such as vertical-cavity surface-emitting lasers, distributed feedback (DFB) lasers, Fabry–Pérot (FP) lasers, or semiconductor lasers embedded with saturable absorbers (SAs) (e.g., FP-SA and DFB-SA). PSNN architectures, including fully connected and convolutional structures, are developed, and supervised and unsupervised learning algorithms that take into account optical constraints are introduced to accomplish specific applications. This work covers devices, architectures, learning algorithms, and applications for photonic and optoelectronic neuromorphic computing and provides our perspective on the challenges and prospects of photonic neuromorphic computing based on semiconductor lasers.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"35 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141778525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chhabindra Gautam, Mingsen Pan, Subhashree Seth, Thomas J. Rotter, Ming Zhou, Bradley J. Thompson, Ricky Gibson, Shanhui Fan, Ganesh Balakrishnan, Weidong Zhou
As a new type of semiconductor laser, photonic crystal surface-emitting lasers (PCSELs) feature large-area single-mode surface emission with high power and high beam quality. The unique features of single-mode lasing over a large area active region are implemented by the in-plane optical feedback from two-dimensional (2D) photonic crystal cavities. In larger PCSEL cavities, the lasing gain threshold becomes similar for the fundamental and high-order modes, which degrades single-mode operation. Here, we investigate the impact of carrier injection on PCSEL modes by controlling the injection area and the gain mode interaction. Optical and electrical simulations are carried out to calculate the gain mode overlapping factor for different p electrode designs. We fabricated 250 × 250 µm2 photonic crystal cavities with different p electrode sizes for injection area control. The PCSEL device characterization results show that devices with an electrode size to cavity side length ratio of 0.6 have the maximum slope efficiency and a lower lasing threshold with a single lobe beam profile. Such selective carrier injection can also provide gain-guided resonance in the PCSEL cavities and enhance optical gain in the fundamental mode while suppressing gain in the high-order modes.
作为一种新型半导体激光器，光子晶体表面发射激光器（PCSEL）具有大面积单模表面发射、高功率和高光束质量的特点。通过二维（2D）光子晶体腔的面内光反馈，实现了大面积有源区单模激光的独特功能。在较大的 PCSEL 腔中，基模和高阶模的激光增益阈值变得相似，从而降低了单模工作性能。在此，我们通过控制注入区域和增益模式相互作用，研究载流子注入对 PCSEL 模式的影响。我们进行了光学和电学模拟，以计算不同 p 电极设计的增益模式重叠系数。我们制作了 250 × 250 µm2 的光子晶体腔，采用不同尺寸的 p 电极来控制注入面积。PCSEL 器件的表征结果表明，电极尺寸与腔体边长比为 0.6 的器件具有最高的斜率效率和较低的激光阈值，并具有单叶光束轮廓。这种选择性载流子注入还能在 PCSEL 腔中产生增益导向共振，并在抑制高阶模式增益的同时提高基阶模式的光学增益。
{"title":"Mode distribution impact on photonic crystal surface emitting laser performance","authors":"Chhabindra Gautam, Mingsen Pan, Subhashree Seth, Thomas J. Rotter, Ming Zhou, Bradley J. Thompson, Ricky Gibson, Shanhui Fan, Ganesh Balakrishnan, Weidong Zhou","doi":"10.1063/5.0199361","DOIUrl":"https://doi.org/10.1063/5.0199361","url":null,"abstract":"As a new type of semiconductor laser, photonic crystal surface-emitting lasers (PCSELs) feature large-area single-mode surface emission with high power and high beam quality. The unique features of single-mode lasing over a large area active region are implemented by the in-plane optical feedback from two-dimensional (2D) photonic crystal cavities. In larger PCSEL cavities, the lasing gain threshold becomes similar for the fundamental and high-order modes, which degrades single-mode operation. Here, we investigate the impact of carrier injection on PCSEL modes by controlling the injection area and the gain mode interaction. Optical and electrical simulations are carried out to calculate the gain mode overlapping factor for different p electrode designs. We fabricated 250 × 250 µm2 photonic crystal cavities with different p electrode sizes for injection area control. The PCSEL device characterization results show that devices with an electrode size to cavity side length ratio of 0.6 have the maximum slope efficiency and a lower lasing threshold with a single lobe beam profile. Such selective carrier injection can also provide gain-guided resonance in the PCSEL cavities and enhance optical gain in the fundamental mode while suppressing gain in the high-order modes.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"16 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ultrasound-induced optical clearing microscopy (US-OCM) addresses limited imaging depth in optical microscopy, caused by light scattering in biological tissues. It uses ultrasound-induced gas bubbles to better image biological samples. However, controlling the bubble location using only ultrasound is challenging. This study introduces a novel method, “optrasound,” combining optical and ultrasound energies for precise bubble control. It presents the ultrasound field and uses a focused laser to trigger bubble formation. Optrasound-induced deep microscopy improves light beam width by 3.39 times at a depth of 350 µm because the gas bubbles reduce light scattering. This technique can precisely localize a bubble cloud while matching the US-OCM performance.
{"title":"Gas bubbles induced by combined optical and ultrasound energies for high-resolution deep optical microscopy","authors":"Jinwoo Kim, Juhwan Kim, Haemin Kim, Jin Ho Chang","doi":"10.1063/5.0203205","DOIUrl":"https://doi.org/10.1063/5.0203205","url":null,"abstract":"Ultrasound-induced optical clearing microscopy (US-OCM) addresses limited imaging depth in optical microscopy, caused by light scattering in biological tissues. It uses ultrasound-induced gas bubbles to better image biological samples. However, controlling the bubble location using only ultrasound is challenging. This study introduces a novel method, “optrasound,” combining optical and ultrasound energies for precise bubble control. It presents the ultrasound field and uses a focused laser to trigger bubble formation. Optrasound-induced deep microscopy improves light beam width by 3.39 times at a depth of 350 µm because the gas bubbles reduce light scattering. This technique can precisely localize a bubble cloud while matching the US-OCM performance.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"78 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we introduce a quantum-secured single-pixel imaging technique designed to withstand spoofing attacks, wherein adversaries attempt to deceive imaging systems with fake signals. Unlike previous quantum-secured protocols that impose a threshold error rate limiting their operation, even with the existence of true signals, our approach not only identifies spoofing attacks but also facilitates the reconstruction of a true image. Our method involves the analysis of a specific mode correlation of a photon-pair, which is independent of the mode used for image construction, to check security. Through this analysis, we can identify both the targeted image region of the attack and the type of spoofing attack, enabling reconstruction of the true image. A proof-of-principle demonstration employing the polarization-correlation of a photon-pair is provided, showcasing successful image reconstruction even under the condition of spoofing signals that are 2000 times stronger than true signals. We expect our approach to be applied to quantum-secured signal processing, such as quantum target detection or ranging.
{"title":"True image construction in quantum-secured single-pixel imaging under spoofing attack","authors":"Jaesung Heo, Taek Jeong, Nam Hun Park, Yonggi Jo","doi":"10.1063/5.0209041","DOIUrl":"https://doi.org/10.1063/5.0209041","url":null,"abstract":"In this paper, we introduce a quantum-secured single-pixel imaging technique designed to withstand spoofing attacks, wherein adversaries attempt to deceive imaging systems with fake signals. Unlike previous quantum-secured protocols that impose a threshold error rate limiting their operation, even with the existence of true signals, our approach not only identifies spoofing attacks but also facilitates the reconstruction of a true image. Our method involves the analysis of a specific mode correlation of a photon-pair, which is independent of the mode used for image construction, to check security. Through this analysis, we can identify both the targeted image region of the attack and the type of spoofing attack, enabling reconstruction of the true image. A proof-of-principle demonstration employing the polarization-correlation of a photon-pair is provided, showcasing successful image reconstruction even under the condition of spoofing signals that are 2000 times stronger than true signals. We expect our approach to be applied to quantum-secured signal processing, such as quantum target detection or ranging.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"21 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141738807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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