{"title":"Hundred-watt level all-fiber visible supercontinuum generation from a graded-index multimode fiber","authors":"Li Jiang, R. Song, J. Hou","doi":"10.3788/col202321.051403","DOIUrl":"https://doi.org/10.3788/col202321.051403","url":null,"abstract":"A monolithic visible supercontinuum (SC) source with a record average output power of 204 W and a spectrum ranging from 580 nm to beyond 2400 nm is achieved in a piece of standard telecom graded-index multimode fiber (GRIN MMF) by designing the pumping system. The influence of the GRIN MMF length on the geometrical parameter instability (GPI) effect is analyzed for the first time, to the best of our knowledge, by comparing the SC spectral region dominated by the GPI effect under different fiber lengths. Our work could pave the way for robust, cost-effective, and high-power visible SC sources.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"51 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83951435","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}
{"title":"Atomic structures and carrier dynamics of defects in a ZnGeP2 crystal","authors":"","doi":"10.3788/col202321.041604","DOIUrl":"https://doi.org/10.3788/col202321.041604","url":null,"abstract":"","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"4 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79499454","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}
{"title":"High-uniformity 2 × 64 silicon avalanche photodiode arrays with silicon multiple epitaxy technology","authors":"Tiancai Wang, Peng Cao, Hongling Peng, Chuanwang Xu, Hai-Xi Song, Wanhua Zheng","doi":"10.3788/col202321.032501","DOIUrl":"https://doi.org/10.3788/col202321.032501","url":null,"abstract":"In this paper, high-uniformity 2 × 64 silicon avalanche photodiode (APD) arrays are reported. Silicon multiple epitaxy technology was used, and the high performance APD arrays based on double-layer epiwafers are achieved for the first time, to the best of our knowledge. A high-uniformity breakdown voltage with a fluctuation of smaller than 3.5 V is obtained for the fabricated APD arrays. The dark currents are below 90 pA for all 128 pixels at unity gain voltage. The pixels in the APD arrays show a gain factor of larger than 300 and a peak responsivity of 0.53 A = W@M= 1 at 850 nm (corresponding to maximum external quantum efficiency of 81%) at room temperature. Quick optical pulse response time was measured, and a corresponding cutoff frequency up to 100 MHz was obtained. dark current.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"274 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79537870","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}
Xiaomei Dong, Yuhan Du, Miaohua Xu, Yutong Li, Zhe Zhang, Yingjun Li
{"title":"Effects of laser waveform on the generation of fast electrons in laser–solid interactions","authors":"Xiaomei Dong, Yuhan Du, Miaohua Xu, Yutong Li, Zhe Zhang, Yingjun Li","doi":"10.3788/col202321.063801","DOIUrl":"https://doi.org/10.3788/col202321.063801","url":null,"abstract":"In the scheme of fast ignition of inertial confinement fusion, the fuel temperature mainly relies on fast electrons, which act as an energy carrier, transferring the laser energy to the fuel. Both conversion efficiency from the laser to the fast electron and the energy spectrum of the fast electron are essentially important to achieve highly effective heating. In this study, a two-dimensional particle in cell simulation is applied to study the generation of fast electrons from solid-density plasmas with different laser waveforms. The results have shown that the slope of the rising edge has a significant effect on fast electron generation and energy absorption. For the negative skew pulse with a relatively slow rising edge, the J × B mechanism can most effectively accelerate the electrons. The overall absorption efficiency of the laser energy is optimized, and the fast electron yield in the middle- and low-energy range is also improved.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"61 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78320815","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}
{"title":"On-chip ultraviolet second-harmonic generation in lithium-tantalate thin film microdisk","authors":"Miao Xue, Xiongshuo Yan, Jiangwei Wu, Rui Ge, Tingge Yuan, Yuping Chen, Xianfeng Chen","doi":"10.3788/col202321.061902","DOIUrl":"https://doi.org/10.3788/col202321.061902","url":null,"abstract":"The compact and reliable ultraviolet (UV) source has attracted remarkable attention for its potential use in optical measurement systems, high-density optical storage, and biomedical applications. We demonstrate ultraviolet generation by frequency doubling in a lithium-tantalate-on-insulator (LTOI) microdisk via modal phase matching. The 50-μ m-diameter microdisk was milled by a focused ion beam (FIB) and followed by chemo-mechanical polishing (CMP) to smooth the disk surface and edge, and the Q-factor reaches 2.74 × 10 5 in the visible band. On-chip UV coherent light with a wavelength of 384.3 nm was achieved, which shows great promise for using LTOIs in integrated ultraviolet source platforms.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"12 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84804805","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}
Wenxin Zhang, Y. Tao, Yangkang Wu, F. Zhu, Wenchao Cai, N. Liu, Qiang Zhao, P. Xue
{"title":"Vibration measurement with frequency modulation single-pixel imaging","authors":"Wenxin Zhang, Y. Tao, Yangkang Wu, F. Zhu, Wenchao Cai, N. Liu, Qiang Zhao, P. Xue","doi":"10.3788/col202321.011102","DOIUrl":"https://doi.org/10.3788/col202321.011102","url":null,"abstract":"Single-pixel imaging can reconstruct the image of the object when the light traveling from the object to the detector is scattered or distorted. Most single-pixel imaging methods only obtain distribution of transmittance or reflectivity of the object. Some methods can obtain extra information, such as color and polarization information. However, there is no method that can get the vibration information when the object is vibrating during the measurement. Vibration information is very important, because unexpected vibration often means the occurrence of abnormal conditions. In this Letter, we introduce a method to obtain vibration information with the frequency modulation single-pixel imaging method. This method uses a light source with a special pattern to illuminate the object and analyzes the frequency of the total light intensity signal transmitted or reflected by the object. Compared to other single-pixel imaging methods, frequency modulation single-pixel imaging can obtain vibration information and maintain high signal-to-noise ratio and has potential on finding out hidden facilities under construction or instruments in work.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"56 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90557472","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}
Qiyu Wang, Zehao Wang, Xiang-Dong Chen, Fangwen Sun
{"title":"Detecting the vector of nanoscale light field with atomic defect","authors":"Qiyu Wang, Zehao Wang, Xiang-Dong Chen, Fangwen Sun","doi":"10.3788/col202321.071202","DOIUrl":"https://doi.org/10.3788/col202321.071202","url":null,"abstract":"Modulation of a vector light field has played an important role in the research of nanophotonics. However, it is still a great challenge to accurately measure the three-dimensional vector distribution at nanoscale. Here, based on the interaction between the light field and atomic-sized nitrogen-vacancy (NV) color center in diamonds, we demonstrate an efficient method for vectorial mapping of the light-field distribution at nanoscale. Single NV centers with different but well-defined symmetry axes are selected and then interact with the same tightly focused light field. The excitation of a single NV center is related to the angle between the NV center axis and the polarization of the light field. Then the fluorescence patterns of different NV centers provide the information on the vectorial light field distribution. Subsequently analyzing the fluorescence patterns with the help of a deep neural network, the intensity and phase of the light-field vectorial components are fully reconstructed with nanometer resolution. The experimental results are in agreement with theoretical calculations. It demonstrates that our method can help to study light – matter interaction at nanoscale and extend the application of vector light fields in research on nanophotonics.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"13 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78812473","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}
{"title":"Femtosecond laser filamentation in simulated atmospheric turbulence [Invited]","authors":"Jiewei Guo, Lu Sun, Yuezheng Wang, Jiayun Xue, Zhi Zhang, Haiyi Liu, Shishi Tao, Wenqi Qian, Pengfei Qi, Lie Lin, Weiwei Liu","doi":"10.3788/col202321.110004","DOIUrl":"https://doi.org/10.3788/col202321.110004","url":null,"abstract":"The effects of turbulence intensity and turbulence region on the distribution of femtosecond laser filaments are experimentally elaborated. Through the ultrasonic signals emitted by the filaments, it is observed that increasing turbulence intensity and an expanding turbulence active region cause an increase in the start position of the filament and a decrease in filament length, which can be well explained by theoretical calculation. It is also observed that the random perturbation of the air refractive index caused by atmospheric turbulence expands the spot size of the filament. Additionally, when the turbulence refractive index structure constant reaches 8.37×10-12 m-2/3, multiple filaments are formed. Furthermore, the standard deviation of the transverse displacement of filament is found to be proportional to the square root of the turbulent structure constant under the experimental turbulence parameters in this paper. These results contribute to the study of femtosecond laser propagation mechanisms in complex atmospheric turbulence conditions.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135612368","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}
{"title":"Recent advances in optical fiber high-temperature sensors and encapsulation technique [Invited]","authors":"æ–‡æ�° å¾�, 强 å�ž, 建桥 æ¢�, 振丞 王, æ´‹ 于, æ´² åŸ","doi":"10.3788/col202321.090007","DOIUrl":"https://doi.org/10.3788/col202321.090007","url":null,"abstract":"In the aerospace field, for aerospace engines and other high-end manufacturing equipment working in extreme environments, like ultrahigh temperatures, high pressure, and high-speed airflow, in situ temperature measurement is of great importance for improving the structure design and achieving the health monitoring and the fault diagnosis of critical parts. Optical fiber sensors have the advantages of small size, easy design, corrosion resistance, anti-electromagnetic interference, and the ability to achieve distributed or quasi-distributed sensing and have broad application prospects for temperature sensing in extreme environments. In this review, first, we introduce the current research status of fiber Bragg grating-type and Fabry–Perot interferometer-type high-temperature sensors. Then we review the optical fiber high-temperature sensor encapsulation techniques, including tubular encapsulation, substrate encapsulation, and metal-embedded encapsulation, and discuss the extreme environmental adaptability of different encapsulation structures. Finally, the critical technological issues that need to be solved for the application of optical fiber sensors in extreme environments are discussed.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135600391","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}
Yongpeng Han, Yangjun Mei, Chang Liu, Li Lao, Yao Yao, Jiahao Xiao, Jiayu Zhao, Yan Peng
{"title":"Core-antiresonance-based terahertz cavities and applications [Invited]","authors":"Yongpeng Han, Yangjun Mei, Chang Liu, Li Lao, Yao Yao, Jiahao Xiao, Jiayu Zhao, Yan Peng","doi":"10.3788/col202321.110005","DOIUrl":"https://doi.org/10.3788/col202321.110005","url":null,"abstract":"This work presents a brief review of our recent research on an antiresonant mechanism named core antiresonant reflection (CARR), which leads to a broadband terahertz (THz) spectrum output with periodic dips at resonant frequencies after its transmission along a hollow-core tubular structure (e.g., a paper tube). The CARR theory relies only on parameters of the tube core (e.g., the inner diameter) rather than the cladding, thus being distinct from existing principles such as the traditional antiresonant reflection inside optical waveguides (ARROWs). We demonstrate that diverse tubular structures, including cylindrical, polyhedral, spiral, meshy, and notched hollow tubes with either transparent or opaque cladding materials, as well as a thick-walled hole, could indeed become CARR-type resonators. Based on this CARR effect, we also perform various applications, such as pressure sensing with paper-folded THz cavities, force/magnetism-driven chiral polarization modulations, and single-pulse measurements of the angular dispersion of THz beams. In future studies, the proposed CARR method promises to support breakthroughs in multiple fields by means of being extended to more kinds of tubular entities for enhancing their interactions with light waves in an antiresonance manner.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135612367","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}