Photonics最新文献_第4页

Dispersive Fourier Transform Spectrometer Based on Mode-Locked Er-Doped Fiber Laser for Ammonia Sensing 基于模式锁定掺铒光纤激光器的色散傅立叶变换光谱仪用于氨传感

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-31 DOI: 10.3390/photonics11010045

Nikolay A. Aprelov, Ilya D. Vatnik, D. Kharenko, Alexey A. Redyuk

引用次数: 0

FSK/ASK Orthogonal Modulation System Based on Novel Noncoherent Detection and Electronic Dispersion Compensation for Short-Reach Optical Communications 基于新型非相干检测和电子色散补偿的 FSK/ASK 正交调制系统，用于短距离光通信

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-31 DOI: 10.3390/photonics11010044

Lei Xin, Xiao Xu, Liuge Du, Jia Zhao

{"title":"FSK/ASK Orthogonal Modulation System Based on Novel Noncoherent Detection and Electronic Dispersion Compensation for Short-Reach Optical Communications","authors":"Lei Xin, Xiao Xu, Liuge Du, Jia Zhao","doi":"10.3390/photonics11010044","DOIUrl":"https://doi.org/10.3390/photonics11010044","url":null,"abstract":"We propose an FSK/ASK orthogonal modulation system based on a novel noncoherent detection (NCD) scheme, aimed at expanding the system capacity for short-reach optical communications cost-effectively. In the transmitter, the FSK optical signal is generated by simple frequency modulation through a directly modulated distributed feedback laser. Subsequently, by utilizing a Mach–Zehnder modulator for ASK modulation, the FSK/ASK optical signal is obtained. The novel and low-complexity NCD receiver consists of an intensity detection branch and a frequency detection branch. The frequency detection branch is composed of an optical differentiator, a photodetector, and frequency extraction circuits. Notably, the proposed NCD scheme overcomes the limitation of the traditional FSK/ASK-NCD receiver stemming from the trade-off between the detected signal quality of the amplitude and frequency. Furthermore, electronic dispersion compensation (EDC) is available. Through numerical simulations, our findings demonstrate that the proposed FSK/ASK-NCD system, assisted by EDC, achieves a remarkable 100 km transmission span for both 40 Gbps 2FSK/2ASK and 60 Gbps 2FSK/4ASK modulation formats, which surpasses the 2ASK-DD and the 4ASK-DD systems, where the maximum achievable spans are limited to less than 20 km. These results underscore the potential of the proposed system as a robust candidate for future passive optical access networks.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"94 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139131768","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

Designing a Long Optical Path Direct-Injection-Integrated Cavity for Laser Absorption Spectroscopy 设计用于激光吸收光谱的长光路直接注入式集成腔体

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-30 DOI: 10.3390/photonics11010036

Quyouyang Gao, Yuquan Zheng, Long Wang, Chengliang Li, Jialun Zhang, Hao Wu, Yanxue Han, Shuo Wang

{"title":"Designing a Long Optical Path Direct-Injection-Integrated Cavity for Laser Absorption Spectroscopy","authors":"Quyouyang Gao, Yuquan Zheng, Long Wang, Chengliang Li, Jialun Zhang, Hao Wu, Yanxue Han, Shuo Wang","doi":"10.3390/photonics11010036","DOIUrl":"https://doi.org/10.3390/photonics11010036","url":null,"abstract":"Trace gas measurement has a wide range of applications needed in industrial, medical, and environmental protection. With the evolution of time, the demand for real-time, sensitivity, and accuracy of gas detection has been increasingly heightened. Off-axis integrated cavity output spectroscopy (OA-ICOS) is an effective method for the high-sensitivity detection of trace gases. It uses an integrated cavity with two highly reflective mirrors to provide a long optical path, which guarantees its high sensitivity. However, as the reflectivity of the mirrors increases, the intensity of the output light decreases, and the signal-to-noise ratio decreases. This contradiction makes it difficult to achieve a long optical path and a high signal-to-noise ratio together. To combat this issue, this paper proposes a type of integrated cavity using a direct-injection method. This structure, under equivalent mirror conditions, can maintain an effective absorption optical path very close to the original off-axis integrated cavity while increasing the output light intensity hundreds of times. This enhancement increases the sensitivity of OA-ICOS.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":" 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139140868","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

Stationary High-Energy Pulse Generation in Er-Based Fiber Lasers via Quasi-Synchronous Gain Modulation 通过准同步增益调制在 Er 型光纤激光器中产生静态高能量脉冲

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-30 DOI: 10.3390/photonics11010037

B. Nyushkov, A. Ivanenko, Natalia Koliada, Sergey Smirnov

{"title":"Stationary High-Energy Pulse Generation in Er-Based Fiber Lasers via Quasi-Synchronous Gain Modulation","authors":"B. Nyushkov, A. Ivanenko, Natalia Koliada, Sergey Smirnov","doi":"10.3390/photonics11010037","DOIUrl":"https://doi.org/10.3390/photonics11010037","url":null,"abstract":"We demonstrate the feasibility of triggering stationary high-energy pulse generation in Er-doped fiber lasers at ~1.5 µm via quasi-synchronous gain modulation. This simple method relies upon the sine-wave modulation of pump power at a frequency slightly surpassing the intrinsic frequency spacing of longitudinal modes in the laser cavity. This was previously implemented only in Yb-doped fiber lasers at ~1.1 µm. Here, for the first time, we experimentally validate the pulse shaping capabilities of this method also in Er fiber lasers, which, unlike Yb fiber lasers, have a three-level laser energy diagram (when pumped at 0.98 µm) with a very long-lived (10 ms) upper laser level. The feasibility of the method was validated both for normal and anomalous intracavity dispersion, which was not available in previous implementations in Yb fiber lasers at ~1.1 µm. Thus, the stable generation of a regular train of discrete nanosecond pulses with an energy of up to 180 nJ was achieved in our test-bed Er fiber laser upon the quasi-synchronous sine-wave modulation of the pump power at 0.98 µm. The results of our study testify to the general applicability of this affordable and reliable method for high-energy pulse generation in various rare-earth-doped fiber lasers.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":" 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139139332","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

382 mW External-Cavity Frequency Doubling 461 nm Laser Based on Quasi-Phase Matching 基于准相位匹配的 382 mW 461 nm 外腔倍频激光器

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-30 DOI: 10.3390/photonics11010040

Yingxin Chen, Guodong Zhao, Wei Tan, Hong Chang

{"title":"382 mW External-Cavity Frequency Doubling 461 nm Laser Based on Quasi-Phase Matching","authors":"Yingxin Chen, Guodong Zhao, Wei Tan, Hong Chang","doi":"10.3390/photonics11010040","DOIUrl":"https://doi.org/10.3390/photonics11010040","url":null,"abstract":"To rapidly improve strontium optical clocks, a high-power, high-efficiency, and high-beam-quality 461 nm laser is required. In blue lasers based on periodically poled KTiOPO4 crystals, the optical absorption in the crystals can induce thermal effects, which must be considered in the design of high-efficiency external-cavity frequency doubling lasers. The interdependence between the absorption and the thermally induced quasi-phase mismatch was taken into account for the solution to the coupled wave equations. By incorporating multilayer crystal approximation, a theoretical model was developed to accurately determine the absorption of the frequency doubling laser. Based on experimental parameters, the temperature gradient in the crystal, the influence of the boundary temperature on the conversion efficiency, and the focal length of the thermal lens were simulated. Theoretical calculations were employed to optimize the parameters of the external-cavity frequency doubling experiment. In the experiment, in a bow-tie external cavity was demonstrated by pumping a 10 mm long periodically poled KTiOPO4 crystal with a 922 nm laser, a 461 nm laser with a maximum output power of 382 mW. The conversion efficiency of the incident fundamental laser was 66.2%. The M2 factor of the frequency doubling beam was approximately 1.4.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":" 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139140792","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

Nonlinear Scattering of 248 nm Wavelength Light in High-Pressure SF6 and CH4 Gases for the Temporal Compression of a 20 ns KrF Laser Pulse 高压 SF6 和 CH4 气体中 248 nm 波长光的非线性散射，用于 20 ns KrF 激光脉冲的时间压缩

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-30 DOI: 10.3390/photonics11010039

V. Zvorykin, G. E. Metreveli, I. Smetanin, A. V. Shutov, N. Ustinovskii, P. V. Veliev

引用次数: 0

NaGdF4:Yb, Er, Tm Upconversion Nanoparticles for Bioimaging in Shortwave-Infrared Range: Study of Energy Transfer Processes and Composition Optimization 用于短波-红外范围生物成像的 NaGdF4:Yb, Er, Tm 上转换纳米粒子：能量转移过程和成分优化研究

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-30 DOI: 10.3390/photonics11010038

D. Pominova, V. Proydakova, I. Romanishkin, Sergei Kuznetsov, Kirill Linkov, Nataliya Tabachkova, A. Ryabova

{"title":"NaGdF4:Yb, Er, Tm Upconversion Nanoparticles for Bioimaging in Shortwave-Infrared Range: Study of Energy Transfer Processes and Composition Optimization","authors":"D. Pominova, V. Proydakova, I. Romanishkin, Sergei Kuznetsov, Kirill Linkov, Nataliya Tabachkova, A. Ryabova","doi":"10.3390/photonics11010038","DOIUrl":"https://doi.org/10.3390/photonics11010038","url":null,"abstract":"Upconversion nanoparticles are promising for many applications. For triple-doped nanoparticles (NPs), the luminescence intensity shows a non-linear dependence on the rare-earth ion concentration, making it difficult to obtain bright phosphors with high energy output. We investigated the energy transfer processes in β-NaGdF4:Yb-Er-Tm NPs and considered strategies for increasing the thulium luminescence intensity, in particular, the use of core–shell structures. The luminescence spectra were analyzed in the short-wavelength infrared (SWIR) and visible (VIS) regions. The Er3+ and Tm3+ luminescence lifetimes in the VIS region were measured to study the energy transfer processes between the active ions. The quenching of the Tm3+ luminescence in the SWIR region was observed. However, both Er3+ and Tm3+ luminescence bands were observed in the VIS range. We attribute these effects to energy transfer between Tm3+ 3F4 → 3H6 and Er3+ 4I13/2 → 4I9/2, which occurs due to overlap of Er3+ and Tm3+ luminescence bands, and also to competition between Er3+ and Tm3+ for energy transfer from Yb3+. For core–shell NPs, when Tm3+ and Er3+ are separated into adjacent layers, quenching cannot be avoided, likely due to the mutual diffusion of ions during shell synthesis. The most optimal strategy to obtain luminescence in the SWIR range is to use an inert intermediate shell between the layers containing Tm3+ and Er3+.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":" 41","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139138458","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

Image Enhancement Method for Photoacoustic Imaging of Deep Brain Tissue 脑深部组织光声成像的图像增强方法

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-29 DOI: 10.3390/photonics11010031

Yonghua Xie, Dan Wu, Xinsheng Wang, Yanting Wen, Jing Zhang, Ying Yang, Yi Chen, Yun Wu, Zihui Chi, Huabei Jiang

{"title":"Image Enhancement Method for Photoacoustic Imaging of Deep Brain Tissue","authors":"Yonghua Xie, Dan Wu, Xinsheng Wang, Yanting Wen, Jing Zhang, Ying Yang, Yi Chen, Yun Wu, Zihui Chi, Huabei Jiang","doi":"10.3390/photonics11010031","DOIUrl":"https://doi.org/10.3390/photonics11010031","url":null,"abstract":"Photoacoustic imaging (PAI) is an emerging biomedical imaging modality, offering numerous advantages, including high resolution and high contrast. In its application to brain imaging, however, the photoacoustic (PA) signals from brain tissue weaken considerably due to the distortion effects of the skull. This attenuation reduces the resolution and contrast significantly. To address this issue, here we describe a Log-MSR algorithm that combines the logarithmic depth logarithmic enhancement (Log) algorithm and the multi-scale Retinex (MSR) algorithm. In this method, the Log algorithm performs local weighted compensation based on signal attenuation for different depths, while the MSR algorithm improves the contrast of the image. The proposed Log-MSR algorithm was tested and validated using several phantom and in vivo experiments. The enhanced images constructed by the Log-MSR algorithm were qualitatively and quantitatively analyzed in terms of brain structure and function. Our results show that the Log-MSR algorithm may provide a significant enhancement to photoacoustic imaging of deep brain tissue.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"48 s168","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139146005","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

Performance of Adaptive Bit-Interleaved Polar Coded Modulation in FSOC System FSOC 系统中的自适应比特交织极性编码调制性能

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-29 DOI: 10.3390/photonics11010034

Qingfang Jiang, Zhi Liu, Haifeng Yao, Zhonglin Luo, Xin Zhang, Shutong Liu, Chenming Cao, Gang Jing, Hao Li, Peng Lin

{"title":"Performance of Adaptive Bit-Interleaved Polar Coded Modulation in FSOC System","authors":"Qingfang Jiang, Zhi Liu, Haifeng Yao, Zhonglin Luo, Xin Zhang, Shutong Liu, Chenming Cao, Gang Jing, Hao Li, Peng Lin","doi":"10.3390/photonics11010034","DOIUrl":"https://doi.org/10.3390/photonics11010034","url":null,"abstract":"This paper proposes an adaptive bit-interleaved polar coded modulation (A-BIPCM) method based on minimum logarithmic upper bound weight (MLUW). It is designed to reduce the fading effects and long string of bit error interference caused by atmospheric turbulence in free-space optical communications (FSOC). To assess the effectiveness of this method across turbulent channels of varying intensities, we conducted an evaluation of the bit error rate (BER) performance of polar codes in turbulent channels. The results demonstrate significant performance improvements provided by the A-BIPCM method compared to conventional polar code encoding and decoding. Specifically, under weak, moderate, and strong turbulence conditions, the A-BIPCM method achieves performance gains of 0.96 dB, 1.66 dB, and 1.35 dB, respectively. Additionally, an experimental verification platform for FSOC employing intensity modulation direct detection (IM/DD) with an atmospheric turbulence simulation channel, is established in this work. When the optical power of the detector is −16 dBm, the traditional polar code encoding and decoding performance at BER = 2.36 × 10−5, whereas the A-BIPCM scheme exhibits a significantly higher performance at BER = 2.11 × 10−6. The BER has been improved by representing an order of magnitude.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"49 s243","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139146718","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

Attitude Determination of Photovoltaic Device by Means of Differential Absorption Imaging 利用差分吸收成像确定光伏设备的姿态

IF 2.4 4区物理与天体物理

Photonics Pub Date : 2023-12-29 DOI: 10.3390/photonics11010032

K. Asaba, Tomoyuki Miyamoto

{"title":"Attitude Determination of Photovoltaic Device by Means of Differential Absorption Imaging","authors":"K. Asaba, Tomoyuki Miyamoto","doi":"10.3390/photonics11010032","DOIUrl":"https://doi.org/10.3390/photonics11010032","url":null,"abstract":"Future wireless power transmission will cover power levels up to kilowatts or more and transmission distances up to the scale of kilometers. With its narrow beam divergence angle, optical wireless power transmission (OWPT) is a promising candidate for such system implementations. In the operation of OWPT, it is necessary to estimate the position, direction (azimuth, elevation), and attitude of the target photovoltaic device before the power supply. The authors have proposed the detection of targets using differential absorption imaging and positioning with a combination of stereo imagery. In the positioning by stereo imagery, a condition regarding the consistency of the left and right images can be defined. This corresponds to the certain value of the exposure time of the image sensor, and this depends on the target’s attitude angle. In this paper, we discuss target attitude estimation using this minimum exposure time at which the integrity measure converges. A physical model was derived under general conditions of target position and experimental configuration. Target attitudes were estimated within an error range of 10 to 15 degrees in approximately 60 degrees range. On the other hand, there is an attitude estimation method based on the apparent size of the target. When using this method to estimate the attitude angle, errors are significantly large for specular and diffuse mixed targets like the PV. The method proposed in this paper is a robust attitude estimation method for the photovoltaic device in OWPT.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":" 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139142916","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