Photonics最新文献_第9页

Polarization-Based De-Scattering Imaging in Turbid Tissue-like Scattering Media 浊组织样散射介质中基于偏振的去散射成像

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-14 DOI: 10.3390/photonics10121374

Shirong Zhang, Jian Liang, Yanru Jiang, Liyong Ren

引用次数: 0

C- and L-Bands Wavelength-Tunable Mode-Locked Fiber Laser C 波段和 L 波段波长可调模式锁定光纤激光器

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-14 DOI: 10.3390/photonics10121379

Jiajing Lang, Cheng Chen, Pu Zhang, Mei Qi, Haowei Chen

引用次数: 0

Influence of the Spectral Composition of Illuminating Light Sources on Biometric and Phytochemical Characteristics of Ocimum basilicum L. 照明光源的光谱成分对欧芹生物计量学和植物化学特征的影响

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-13 DOI: 10.3390/photonics10121369

Mariya Degtereva, Yevgeniy Levin, Anastasia Gubina, Aleksandr E. Degterev, Ivan Lamkin, G. Konoplev, Sergey Tarasov, Andrei Whaley, A. Whaley, I. Suloev, A. Danilova, K. Gusev, D. Maimistov

{"title":"Influence of the Spectral Composition of Illuminating Light Sources on Biometric and Phytochemical Characteristics of Ocimum basilicum L.","authors":"Mariya Degtereva, Yevgeniy Levin, Anastasia Gubina, Aleksandr E. Degterev, Ivan Lamkin, G. Konoplev, Sergey Tarasov, Andrei Whaley, A. Whaley, I. Suloev, A. Danilova, K. Gusev, D. Maimistov","doi":"10.3390/photonics10121369","DOIUrl":"https://doi.org/10.3390/photonics10121369","url":null,"abstract":"Precise adaptation of the greenhouse lighting spectrum to basic photophysiological processes can effectively and directionally stimulate plant growth and development. The optimal spectrum depends on the plant species and the stage of development and could be assessed empirically. The aim of this study is to determine the LED illumination spectrum that provides a significant improvement in the growth rate and accumulation of biologically active compounds for basil plants (Ocimum basilicum L.) under hydroponic cultivation compared to more traditional lighting sources. The following light sources with various emission spectra were used: an LED lamp within a spectral range of 400–800 nm (B:G:R 15%:5%:80%); a high-pressure sodium lamp (HPS) (B:G:R 5%:45%:50%); a compact fluorescent lamp (B:G:R 20%:40%:40%); a grow LED strip (B:G:R 15%:40%:45%); a white LED lamp (B:G:R 30%:45%:25%); a customized LED lighting setup in color ratios 100%B, 75%B + 25%R, 50%B + 50%R, 25%B + 75%R, 100%R, and natural lighting. A photosynthetic photon flux density (PPFD) of 150 μmol∙m−2∙s−1 was provided with all the sources. It was demonstrated reliably that employing the LED strip as an illumination device gives a 112% increase in basil plant yield compared to the HPS; the transpiration coefficient for the LED strip is six times lower than for the HPS. The content of flavonoids in the basil aerial parts on the 30th, 50th, and 70th days of development is 3.2 times higher than for the HPS; the metabolite composition is also more uniform for LED strip lighting.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"56 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138976493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Mode-Independent Optical Switch Based on Graphene-Polymer Hybrid Waveguides 基于石墨烯-聚合物混合波导的模式无关光开关

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-13 DOI: 10.3390/photonics10121372

Tianhang Lian, Yuhang Xie, Qidong Yu, Shijie Sun, Xiaoqiang Sun, Xi-bin Wang, Daming Zhang

{"title":"Mode-Independent Optical Switch Based on Graphene-Polymer Hybrid Waveguides","authors":"Tianhang Lian, Yuhang Xie, Qidong Yu, Shijie Sun, Xiaoqiang Sun, Xi-bin Wang, Daming Zhang","doi":"10.3390/photonics10121372","DOIUrl":"https://doi.org/10.3390/photonics10121372","url":null,"abstract":"Mode-division multiplexing (MDM) is a promising multiplexing technique to further improve the transmission capacity of optical communication and on-chip optical interconnection systems. Furthermore, the multimode optical switch is of great importance in the MDM system, since it makes the MDM system more flexible by directly switching multiple spatial signals simultaneously. In this paper, we proposed a mode-independent optical switch based on the graphene–polymer hybrid waveguide platform that could process the TE11, TE12, TE21 and TE22 modes in a few-mode waveguide. The presented switch is independent of the four guided modes, optimizing the buried position of graphene capacitors in the polymer waveguide to regulate the coplanar interaction between the graphene capacitors and spatial modes. The TE11, TE12, TE21 and TE22 modes can be regulated simultaneously by changing the chemical potential of graphene capacitors in a straight waveguide. Our presented switch can enable the independent management of the spatial modes to be more flexible and efficient and has wide application in the MDM transmission systems.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"183 S477","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139006451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

The Birefringence and Extinction Coefficient of Ferroelectric Liquid Crystals in the Terahertz Range 太赫兹范围内铁电液晶的双折射和消光系数

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-13 DOI: 10.3390/photonics10121368

Ying Ma, Yuhang Shan, Yongning Cheng, Ruisheng Yang, H. Kwok, Jianlin Zhao

引用次数: 0

Special Issue on Photonic State Tomography: Methods and Applications 光子态断层摄影特刊：方法与应用

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-13 DOI: 10.3390/photonics10121370

A. Czerwinski

引用次数: 0

Reinforcement Learning Environment for Wavefront Sensorless Adaptive Optics in Single-Mode Fiber Coupled Optical Satellite Communications Downlinks 单模光纤耦合光学卫星通信下行链路中波前无传感器自适应光学的强化学习环境

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-13 DOI: 10.3390/photonics10121371

Payam Parvizi, Runnan Zou, Colin Bellinger, R. Cheriton, Davide Spinello

{"title":"Reinforcement Learning Environment for Wavefront Sensorless Adaptive Optics in Single-Mode Fiber Coupled Optical Satellite Communications Downlinks","authors":"Payam Parvizi, Runnan Zou, Colin Bellinger, R. Cheriton, Davide Spinello","doi":"10.3390/photonics10121371","DOIUrl":"https://doi.org/10.3390/photonics10121371","url":null,"abstract":"Optical satellite communications (OSC) downlinks can support much higher bandwidths than radio-frequency channels. However, atmospheric turbulence degrades the optical beam wavefront, leading to reduced data transfer rates. In this study, we propose using reinforcement learning (RL) as a lower-cost alternative to standard wavefront sensor-based solutions. We estimate that RL has the potential to reduce system latency, while lowering system costs by omitting the wavefront sensor and low-latency wavefront processing electronics. This is achieved by adopting a control policy learned through interactions with a cost-effective and ultra-fast readout of a low-dimensional photodetector array, rather than relying on a wavefront phase profiling camera. However, RL-based wavefront sensorless adaptive optics (AO) for OSC downlinks faces challenges relating to prediction latency, sample efficiency, and adaptability. To gain a deeper insight into these challenges, we have developed and shared the first OSC downlink RL environment and evaluated a diverse set of deep RL algorithms in the environment. Our results indicate that the Proximal Policy Optimization (PPO) algorithm outperforms the Soft Actor–Critic (SAC) and Deep Deterministic Policy Gradient (DDPG) algorithms. Moreover, PPO converges to within 86% of the maximum performance achievable by the predominant Shack–Hartmann wavefront sensor-based AO system. Our findings indicate the potential of RL in replacing wavefront sensor-based AO while reducing the cost of OSC downlinks.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"119 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139004486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Extension of Fiber Bragg Grating Ultrasound Sensor Network by Adhesive Couplers 通过粘合耦合器扩展光纤布拉格光栅超声波传感器网络

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-12 DOI: 10.3390/photonics10121366

J. Kim, S. Aboubakr, Kara Peters

引用次数: 0

Measurement of the Optical Path Difference Caused by Steering Mirror Using an Equal-Arm Heterodyne Interferometer 利用等臂异调干涉仪测量转向镜造成的光程差

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-11 DOI: 10.3390/photonics10121365

Weizhou Zhu, Yue Guo, Qiyi Jin, Xue Wang, Xingguang Qian, Yong Xie, Lingqiang Meng, Jianjun Jia

引用次数: 0

Physical and Technological Aspects of Laser-Induced Damage of ZGP Single Crystals under Periodically Pulsed Laser Irradiation at 2.1 μm 2.1 μm 周期性脉冲激光辐照下 ZGP 单晶体激光诱导损伤的物理和技术问题

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-11 DOI: 10.3390/photonics10121364

N. Yudin, Victor Dyomin, Alexander Gribenyukov, Oleg Antipov, Andrei Khudoley, I. Kinyaevskiy, Mikhail Zinovev, S. Podzyvalov, V. Kuznetsov, E. Slyunko, Alexey Lysenko, A. Kalsin, I. Eranov, H. Baalbaki

{"title":"Physical and Technological Aspects of Laser-Induced Damage of ZGP Single Crystals under Periodically Pulsed Laser Irradiation at 2.1 μm","authors":"N. Yudin, Victor Dyomin, Alexander Gribenyukov, Oleg Antipov, Andrei Khudoley, I. Kinyaevskiy, Mikhail Zinovev, S. Podzyvalov, V. Kuznetsov, E. Slyunko, Alexey Lysenko, A. Kalsin, I. Eranov, H. Baalbaki","doi":"10.3390/photonics10121364","DOIUrl":"https://doi.org/10.3390/photonics10121364","url":null,"abstract":"The nonlinear properties of zinc germanium diphosphide (ZGP) crystals enable their applications in powerful mid-IR optical parametric oscillators and second-harmonic generators. This paper summarizes the mechanisms of the laser-induced damage (LID) of high-purity ZGP crystals under periodically pulsed nanosecond irradiation by a Ho3+:YAG laser at 2.1 μm. The ZGP samples were manufactured by “LOC” Ent., Tomsk, Russia, or the Harbin Institute of Technology, China. The impact of processing techniques and the post-growing methods for polishing and anti-reflective coatings on the LID threshold are discussed. The importance of the defect structure of the crystal lattice and the parameters of transparent coatings for increasing the LID threshold are also discussed. The impact of the test laser parameters on the LID threshold and the transient area near the LID threshold obtained using digital holography are analyzed. The influence of the pre-damage processes on the optical parametric oscillations is reported. Lastly, the prospects for improving ZGP crystals to further increase the LID threshold are discussed.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"55 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139010409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0