Optics and Laser Technology最新文献_第7页

Machine learning-based mitigation of thermal and nonlinear impairments in optical communication grids 基于机器学习的光通信电网热损伤和非线性损伤缓解技术

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112090

Farman Ali , Haleem Afsar , Ali Alshamrani , Ammar Armghan

{"title":"Machine learning-based mitigation of thermal and nonlinear impairments in optical communication grids","authors":"Farman Ali , Haleem Afsar , Ali Alshamrani , Ammar Armghan","doi":"10.1016/j.optlastec.2024.112090","DOIUrl":"10.1016/j.optlastec.2024.112090","url":null,"abstract":"<div><div>Nonlinear impairments (NIs) act as limiting factors in the performance of long-haul optical communication grids (OCGs), particularly when operating at 100 Gbps over many channels. These deficiencies become worse by the thermal optics effect, which alter the refractive index of optical components and medium leading to signal degradation . This paper introduces a machine learning (ML)-enhanced technique that uses a convolutional neural network (CNN) to reduce distortions induced by NIs while taking thermal dynamics into account. We expand our investigation to evaluate the quality of service of OCGs under the dual impact of NIs and thermal variations, employing advanced modulation schemes such as polarization division multiplexing 64 quadrature amplitude modulation (PDM-64QAM) and dual-polarization quadrature phase-shift keying (DP-QPSK). Extensive simulations, using a split-step Fourier (SSF) method, are performed to model the combined effects of NIs and thermal dynamics on optical signals. Our methodology is supported by stochastic analysis, which simulates the network’s performance while focusing on activation functions that account for thermal impacts on NIs. Our results show that the CNN-based method, in conjunction with advanced modulation schemes, significantly reduces bit error rate (BER) and improves signal-to-noise ratio (SNR), outperforming traditional methods such as support vector machines (SVM) and digital backpropagation (DBP). The proposed approach demonstrates the potential to enhance the quality of transmission (QoT) in OCGs, making it a viable solution for future high-capacity, thermally influenced optical networks.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112090"},"PeriodicalIF":4.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142701278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Effect of enclosed space pressure on thermal regeneration of hydrogen-loaded fiber Bragg gratings 封闭空间压力对含氢光纤布拉格光栅热再生的影响

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112119

Jiajin Zheng , Rubing Bai , Yundi Wang , Junyu Lu , Jianwen Zhou , Zengya Zhang , Shanshan Cao , Wei Li , Kehan Yu , Wei Wei

{"title":"Effect of enclosed space pressure on thermal regeneration of hydrogen-loaded fiber Bragg gratings","authors":"Jiajin Zheng , Rubing Bai , Yundi Wang , Junyu Lu , Jianwen Zhou , Zengya Zhang , Shanshan Cao , Wei Li , Kehan Yu , Wei Wei","doi":"10.1016/j.optlastec.2024.112119","DOIUrl":"10.1016/j.optlastec.2024.112119","url":null,"abstract":"<div><div>The type-I fiber Bragg grating (FBG) was annealed at high temperature to obtain a thermally regenerated fiber Bragg gratings, which can operate reliably in the environments above 1100 °C without any decay of the grating spectrum. However, the underlying thermal regeneration mechanism of FBG has remained unclear until now. Here the thermal regeneration mechanism of FBG was discussed by studying the phenomenon of high-temperature decay and regeneration of FBG in an enclosed space. The thermal decay and regeneration processes of FBGs encapsulated in different volumes were investigated experimentally. The experimental results confirm that hydrogen stored in the hydrogen-loaded fiber diffuses out and then increasing pressure of the enclosed space during the high-temperature regeneration and annealing process of packaged FBG. Once this pressure reaches 0.9 MPa, FBG cannot be regenerated successfully. Comparative analysis with existing regeneration mechanisms reveals that the fundamental cause of thermal regeneration for FBG tends to follow a stress-induced model. However, external pressure affects the periodic distribution of refractive index associated with stress-induced regeneration. When pressure within the confined space reaches a certain critical value, the periodic distribution of stress for FBG will be affected, thus inhibiting the regeneration of FBG.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112119"},"PeriodicalIF":4.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Slit shaping technique for femtosecond laser direct write fabrication of two-dimensional symmetric waveguide arrays in silica glass 用于飞秒激光直接写入制造硅玻璃二维对称波导阵列的狭缝整形技术

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112146

Yuanxin Tan , Haotian Lv , Zengrun Wen , Guanhuai Cheng , Zongcheng Mou , Huaiyi Luo , Yingying Ren , Yang Song , Jian Xu , Ya Cheng , Yangjian Cai

引用次数: 0

Temporal and spatial distribution characteristics of crosstalk line generated by irradiating CCD with nanosecond pulse laser 用纳秒脉冲激光照射 CCD 产生的串扰线的时间和空间分布特征

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112168

Chenghao Yu, Jifei Ye, Hao Chang, Nanlei Li, Ying Wang, Wei Guo

{"title":"Temporal and spatial distribution characteristics of crosstalk line generated by irradiating CCD with nanosecond pulse laser","authors":"Chenghao Yu, Jifei Ye, Hao Chang, Nanlei Li, Ying Wang, Wei Guo","doi":"10.1016/j.optlastec.2024.112168","DOIUrl":"10.1016/j.optlastec.2024.112168","url":null,"abstract":"<div><div>To investigate how a short-pulse laser impacts a charge coupled device (CCD), a laser with a 532 nm wavelength and an 8 ns pulse duration was employed to irradiate the CCD. Images formed by targeting representative CCD locations with a nanosecond pulse laser at various delay intervals were documented. Laser spots become visible in the resulting images if the CCD is exposed to the laser before the process of the readout transfer is completed. The count of saturated pixels in the laser spot, as the laser fluence rises, can be categorized into three parts. In addition, owing to the effect of channel barriers between adjacent vertical charge-transport channels, the length of the crosstalk line in the vertical direction is greater than that in the horizontal direction, and the difference becomes more obvious with increasing laser fluence. Moreover, the dimensions of the crosstalk lines were estimated theoretically. Besides, the experimental findings indicate that the spatial arrangement of the laser spot and the crosstalk line are influenced by two factors: the irradiation location and the delay duration. Nevertheless, the influences of the two elements on the spatial arrangement of the laser spot are separate, whereas their impacts on that of the crosstalk line are interconnected.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112168"},"PeriodicalIF":4.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Advanced chromatic confocal optical coherence tomography sensor with switchable acquisition modes 可切换采集模式的先进色度共焦光学相干断层成像传感器

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112182

Zhun Wang, Zihao Ni, Yulei Bai, Shengli Xie, Bo Dong

{"title":"Advanced chromatic confocal optical coherence tomography sensor with switchable acquisition modes","authors":"Zhun Wang, Zihao Ni, Yulei Bai, Shengli Xie, Bo Dong","doi":"10.1016/j.optlastec.2024.112182","DOIUrl":"10.1016/j.optlastec.2024.112182","url":null,"abstract":"<div><div>A fiber optic sensor combining the principle of chromatic confocal and spectral-domain optical coherence tomography (OCT) has been developed to simultaneously measure film thickness and refractive index. By capturing a spectrum that composed of the low-frequency confocal signal and the high-frequency interference signal, the sensor can initially estimate the confocal thickness and optical thickness of the tested film. Further, by combining the parameter of sensor system, the geometric thickness and refractive index of the film can be subsequently calculated. Additionally, an acquisition mode switching method and a covariance algorithm-based method were also presented to overcome the decrease in signal-to-noise ratio (SNR) induced by signal separation and the reduction in resolution caused by bandwidth narrowing. For validation, five PVC films with different thickness (0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, and 0.5 mm) and five 0.1 mm thickness films with different materials (PVC, PC, PMMA, PET, and FEP) were measured by the sensor. The results indicate that the absolute errors in thickness and refractive index measurements of the sensor are less than 2.5 % and 3.0 %, respectively.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112182"},"PeriodicalIF":4.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142701280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Thermal conductivity and thermo-optic coefficient measurements of transparent thin films using quantitative phase microscopy 利用定量相显微镜测量透明薄膜的导热系数和热光学系数

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112128

Nicholaus Kevin Tanjaya , Takahiro Baba , Masataka Imura , Takao Mori , Satoshi Ishii

引用次数: 0

Iterative orthogonal normalization algorithm for improving phase retrieval accuracy 提高相位检索精度的迭代正交归一化算法

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-22 DOI: 10.1016/j.optlastec.2024.112178

Qinnan Zhang , Shaoke Li , Yifei Chen , Tianyun Liu , Guangshuo Cai , Jiaosheng Li

{"title":"Iterative orthogonal normalization algorithm for improving phase retrieval accuracy","authors":"Qinnan Zhang , Shaoke Li , Yifei Chen , Tianyun Liu , Guangshuo Cai , Jiaosheng Li","doi":"10.1016/j.optlastec.2024.112178","DOIUrl":"10.1016/j.optlastec.2024.112178","url":null,"abstract":"<div><div>The reliance on approximation conditions in conventional orthogonal normalization methods often restricts their accuracy and range of applicability in phase extraction. Consequently, this paper proposes an iterative orthogonal normalization algorithm (IONA) designed specifically for achieving accurate phase retrieval. Unlike traditional orthogonal decomposition methods, this method does not use orthogonal approximation conditions but obtains the correct phase distribution by solving the iterative equation of the phase, transforming the phase solving problem into a loss function minimization problem of the phase distribution. This approach breaks through the limitations of traditional orthogonal methods and can accurately retrieve the phase from the interferograms with less than one stripe. In addition to outperforming existing phase-shifting techniques in accuracy and computational efficiency, the introduced IONA not only negates the requirement for specific fringe counts and configurations but also boasts remarkable stability. Simulation analysis and experimental results indicate that it is a robust and stable solution for phase extraction from fringe patterns with unknown phase shifts.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112178"},"PeriodicalIF":4.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142701279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Quasi-bound states-driven terahertz molecular fingerprint retriever 准结合态驱动的太赫兹分子指纹检索器

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-21 DOI: 10.1016/j.optlastec.2024.112139

Chenglin Yang , Zhonglei Shen , Donghai Han , Yushan Hou , Xin Ji , Liuyang Zhang , Ruqiang Yan , Xuefeng Chen

引用次数: 0

Fast spectrum reconstruction based-on interpretable network with physical model involved 基于涉及物理模型的可解释网络的快速频谱重建

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-20 DOI: 10.1016/j.optlastec.2024.112079

Xinyu Su , Shuangli Liu , Hui Wu , Peng Chen , Jiangnan Yang , Jingjun Wu

{"title":"Fast spectrum reconstruction based-on interpretable network with physical model involved","authors":"Xinyu Su , Shuangli Liu , Hui Wu , Peng Chen , Jiangnan Yang , Jingjun Wu","doi":"10.1016/j.optlastec.2024.112079","DOIUrl":"10.1016/j.optlastec.2024.112079","url":null,"abstract":"<div><div>Computational spectrometers has a great potential for real-time detection in site measurements. Reconstruction algorithms play a pivotal role. Traditional reconstruction algorithms, while demanding low computational resources and enabling real-time measurements, often face challenges in achieving high reconstruction accuracy. Deep learning-based methods offer high-precision reconstruction but require more computational resources and lack interpretability. In this work, we propose an end-to-end interpretable unfolding network that translates the iterative process of the ADMM algorithm into a network layer and autonomously learns sparse basis matrices, ensuring that each network parameter has a clear physical meaning. The performance of this algorithm was validated on two synthetic spectrum datasets and a measured spectrum dataset. The results demonstrate that our method not only ensures high reconstruction accuracy and robustness but also reduces the computational resources. Collectively, this algorithm avoids the black-box characteristics of neural networks and is with physical model involved, which has significant potential to enable high-precision real-time measurements in computational spectroscopy.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112079"},"PeriodicalIF":4.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142701304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Crystallization behavior of amorphous GST films under an ultrafast laser irradiation 超快激光照射下非晶态 GST 薄膜的结晶行为

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-11-20 DOI: 10.1016/j.optlastec.2024.112145

Xuechen Zhang , Jing Lv , Jinlong Xu , Liang Xie , Guodong Zhang , Zhongyin Zhang , Shujuan Li , Guanghua Cheng

{"title":"Crystallization behavior of amorphous GST films under an ultrafast laser irradiation","authors":"Xuechen Zhang , Jing Lv , Jinlong Xu , Liang Xie , Guodong Zhang , Zhongyin Zhang , Shujuan Li , Guanghua Cheng","doi":"10.1016/j.optlastec.2024.112145","DOIUrl":"10.1016/j.optlastec.2024.112145","url":null,"abstract":"<div><div>The crystallization behaviors of amorphous Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> films induced by an ultrafast laser with a time-shaping Gaussian intensity distribution have been studied. The crystalline regions were characterized using optical microscopy, scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. It is found that the region ablated by a single pulse undergoes recrystallization, with a reflectivity higher than that of the non-ablated crystalline region. While preserving the integrity of the film, the diameter of the region with high and uniform reflectivity induced by burst mode is twice that of a single pulse, and the reflectivity is 3 % higher than the 31 % achieved with a single pulse. Additionally, the energy window for laser-induced crystallization expands with an increasing number of burst pulses; specifically, it increases by approximately 2.4 times when the number of sub-pulses is 4 or 5. The Raman results at low pulse energy show a high peak intensity at the 105 cm<sup>−1</sup> in related to the vibrations of Te-rich tetrahedra, indicating that the degree of crystallinity in the burst mode region is superior to that achieved with single pulse irradiation. Furthermore, the blue shift of this Raman peak with increased pulse energy further supports that burst mode provides sufficient time for nucleation growth. This work offers insights into achieving more controllable crystallization, which can enhance its applications in phase change memory and other reconfigurable devices.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"182 ","pages":"Article 112145"},"PeriodicalIF":4.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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