Pub Date : 2023-12-16DOI: 10.3390/photonics10121384
Meet Kumari, Mai Banawan, Vivek Arya, Satyendra Kumar Mishra
Fifth-generation (5G) technology has enabled faster communication speeds, lower latency, a broader range of coverage, and greater capacity. This research aims to introduce a bidirectional high-speed passive optical network (HS-PON) for 5G applications and services including mobile computing, cloud computing, and fiber wireless convergence. Using 16-ary quadrature amplitude modulation orthogonal frequency division multiplexing techniques, the system transmits uplinks and downlinks with a pair of four wavelengths each. Light fidelity (LiFi) services are provided with blue light-emitting-diode-based technology. With a threshold bit error rate (BER) of 10−3, the results demonstrate reliable transportation over a 100 km fiber at −17 dBm received power and in a maximum LiFi range of 20 m. Furthermore, the system offers symmetric 4 × 50 Gbps transmission rates under the impact of fiber–LiFi channel impairments with maximum irradiance and incidence half-angles of 500. Additionally, at threshold BER, the system provides a detection surface range from 1.5 to 4 cm2. Compared to existing networks, the system also provides a high gain and low noise figure. A number of features make this system an attractive option. These include its high speed, high reach, high split ratio, low cost, easy upgradeability, pay-as-you-grow properties, high reliability, and ability to accommodate a large number of users.
{"title":"Investigation of OFDM-Based HS-PON Using Front-End LiFiSystem for 5G Networks","authors":"Meet Kumari, Mai Banawan, Vivek Arya, Satyendra Kumar Mishra","doi":"10.3390/photonics10121384","DOIUrl":"https://doi.org/10.3390/photonics10121384","url":null,"abstract":"Fifth-generation (5G) technology has enabled faster communication speeds, lower latency, a broader range of coverage, and greater capacity. This research aims to introduce a bidirectional high-speed passive optical network (HS-PON) for 5G applications and services including mobile computing, cloud computing, and fiber wireless convergence. Using 16-ary quadrature amplitude modulation orthogonal frequency division multiplexing techniques, the system transmits uplinks and downlinks with a pair of four wavelengths each. Light fidelity (LiFi) services are provided with blue light-emitting-diode-based technology. With a threshold bit error rate (BER) of 10−3, the results demonstrate reliable transportation over a 100 km fiber at −17 dBm received power and in a maximum LiFi range of 20 m. Furthermore, the system offers symmetric 4 × 50 Gbps transmission rates under the impact of fiber–LiFi channel impairments with maximum irradiance and incidence half-angles of 500. Additionally, at threshold BER, the system provides a detection surface range from 1.5 to 4 cm2. Compared to existing networks, the system also provides a high gain and low noise figure. A number of features make this system an attractive option. These include its high speed, high reach, high split ratio, low cost, easy upgradeability, pay-as-you-grow properties, high reliability, and ability to accommodate a large number of users.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"42 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138967760","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}
We have experimentally created perfect vortex beams (PVBs) by Fourier transformation of Bessel–Gaussian vortex beams, which are generated by modulating the fundamental Gaussian beam with the spiral phase plates and the axicons, respectively. Although the method has been used many times by other authors, as far as we know, few people pay attention to the quantitative relationship between the control parameters of the PVB and ring width. The effects of the waist radius of the fundamental Gaussian beam wg, base angle of the axicon γ, and focal length of the lens f on the spot parameters (ring radius ρ, and ring half-width Δ) of PVB are systematically studied. The beam pattern of the generated Bessel–Gaussian beam for different propagation distances behind the axicon and the fundamental Gaussian beam wg is presented. We showed experimentally that the ring radius ρ increases linearly with the increase of the base angle γ and focal length f, while the ring half-width Δ decreases with the increase of the fundamental beam waist radius wg, and increases with enlarging the focal length f. We confirmed the topological charge (TC) of the PVB by the interferogram between the PVB and the reference fundamental Gaussian beam. We also studied experimentally that the size of the generated PVB in the Fourier plane is independent of the TCs. Our approach to generate the PVB has the advantages of high-power tolerance and high efficiency.
我们通过对贝塞尔-高斯涡旋束进行傅里叶变换,在实验中产生了完美涡旋束(PVB),它是分别用螺旋相板和轴子对基本高斯束进行调制而产生的。虽然该方法已被其他学者多次使用,但就我们所知,很少有人关注 PVB 控制参数与环宽之间的定量关系。本文系统地研究了基本高斯光束腰半径 wg、轴心基角 γ 和透镜焦距 f 对 PVB 光斑参数(环半径 ρ 和环半宽 Δ)的影响。我们展示了在不同传播距离下产生的贝塞尔-高斯光束的光束模式,以及基本高斯光束 wg。实验表明,环半径 ρ 随基角 γ 和焦距 f 的增大而线性增大,环半宽 Δ 随基波束腰半径 wg 的增大而减小,随焦距 f 的增大而增大。我们还通过实验研究发现,在傅立叶平面上生成的 PVB 的大小与 TC 无关。我们生成 PVB 的方法具有高功率容限和高效率的优点。
{"title":"Generation of Perfect Vortex Beams with Complete Control over the Ring Radius and Ring Width","authors":"Xin Tao, Yong Liang, Shirui Zhang, Yueqing Li, Minghao Guo, Peng Li","doi":"10.3390/photonics10121382","DOIUrl":"https://doi.org/10.3390/photonics10121382","url":null,"abstract":"We have experimentally created perfect vortex beams (PVBs) by Fourier transformation of Bessel–Gaussian vortex beams, which are generated by modulating the fundamental Gaussian beam with the spiral phase plates and the axicons, respectively. Although the method has been used many times by other authors, as far as we know, few people pay attention to the quantitative relationship between the control parameters of the PVB and ring width. The effects of the waist radius of the fundamental Gaussian beam wg, base angle of the axicon γ, and focal length of the lens f on the spot parameters (ring radius ρ, and ring half-width Δ) of PVB are systematically studied. The beam pattern of the generated Bessel–Gaussian beam for different propagation distances behind the axicon and the fundamental Gaussian beam wg is presented. We showed experimentally that the ring radius ρ increases linearly with the increase of the base angle γ and focal length f, while the ring half-width Δ decreases with the increase of the fundamental beam waist radius wg, and increases with enlarging the focal length f. We confirmed the topological charge (TC) of the PVB by the interferogram between the PVB and the reference fundamental Gaussian beam. We also studied experimentally that the size of the generated PVB in the Fourier plane is independent of the TCs. Our approach to generate the PVB has the advantages of high-power tolerance and high efficiency.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"4 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139000901","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}
Pub Date : 2023-12-15DOI: 10.3390/photonics10121383
M. Likhachev, T.S. Zaushitsyna, Vitaliya A. Agakhanova, Liudmila D. Iskhakova, S. Aleshkina, M. Bubnov, Alexey S. Lobanov, D. Lipatov
A significant change in the refractive index profiles for the large mode area phosphoroaluminosilicate (PAS) core optical fibers was observed in comparison to that in preforms. This study shows that the refractive index of the PAS core can vary from negative (in preform) to positive (in fiber), and the difference in the refractive index between the core and preform can exceed a few thousand. By measuring a large set of fibers with different concentrations of P2O5 and Al2O3, we define the refractivity of each dopant (P2O5, Al2O3 and AlPO4 joint) after drawing fiber from the preform and discuss the possible origin of the observed refractive index variation.
{"title":"Refractivity of P2O5-Al2O3-SiO2 Glass in Optical Fibers","authors":"M. Likhachev, T.S. Zaushitsyna, Vitaliya A. Agakhanova, Liudmila D. Iskhakova, S. Aleshkina, M. Bubnov, Alexey S. Lobanov, D. Lipatov","doi":"10.3390/photonics10121383","DOIUrl":"https://doi.org/10.3390/photonics10121383","url":null,"abstract":"A significant change in the refractive index profiles for the large mode area phosphoroaluminosilicate (PAS) core optical fibers was observed in comparison to that in preforms. This study shows that the refractive index of the PAS core can vary from negative (in preform) to positive (in fiber), and the difference in the refractive index between the core and preform can exceed a few thousand. By measuring a large set of fibers with different concentrations of P2O5 and Al2O3, we define the refractivity of each dopant (P2O5, Al2O3 and AlPO4 joint) after drawing fiber from the preform and discuss the possible origin of the observed refractive index variation.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"130 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138996995","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}
Pub Date : 2023-12-15DOI: 10.3390/photonics10121380
Yuhua Li, Zhe Kang, W. Ho, R. Davidson, B. Little, S. Chu, Kun Zhu
All-optical radio-frequency spectrum analyzers (AORFSAs) with ultrabroad bandwidth break the electronic bottleneck and provide an efficient frequency analysis means for ultrafast optical signals in communications, signal generation and processing systems. Here, we propose and experimentally demonstrate an AORFSA built on the cross-phase modulation effect in a 50 cm long CMOS-compatible photonic slot-waveguide. The waveguide has a 100 nm thick thin-film core of fused silica that is sandwiched by two 750 nm thick cladding layers of high-index doped silica, which shows optimized dispersion and comparable nonlinear characteristics. The measured 3 dB bandwidth of the proposed slot-waveguide-based AORFSA has a three-fold increase over the conventional channel waveguide having the same dimension and length. The sensitivity and wavelength- and polarization-dependence properties are investigated, confirming the proposed waveguide as a versatile platform for frequency analysis of ultrafast optical signals, such as Kerr microcombs with hundreds of GHz or even THz mode spacing.
{"title":"Slot-Waveguide Based All-Optical RF Spectrum Analyzer","authors":"Yuhua Li, Zhe Kang, W. Ho, R. Davidson, B. Little, S. Chu, Kun Zhu","doi":"10.3390/photonics10121380","DOIUrl":"https://doi.org/10.3390/photonics10121380","url":null,"abstract":"All-optical radio-frequency spectrum analyzers (AORFSAs) with ultrabroad bandwidth break the electronic bottleneck and provide an efficient frequency analysis means for ultrafast optical signals in communications, signal generation and processing systems. Here, we propose and experimentally demonstrate an AORFSA built on the cross-phase modulation effect in a 50 cm long CMOS-compatible photonic slot-waveguide. The waveguide has a 100 nm thick thin-film core of fused silica that is sandwiched by two 750 nm thick cladding layers of high-index doped silica, which shows optimized dispersion and comparable nonlinear characteristics. The measured 3 dB bandwidth of the proposed slot-waveguide-based AORFSA has a three-fold increase over the conventional channel waveguide having the same dimension and length. The sensitivity and wavelength- and polarization-dependence properties are investigated, confirming the proposed waveguide as a versatile platform for frequency analysis of ultrafast optical signals, such as Kerr microcombs with hundreds of GHz or even THz mode spacing.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"2 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138997842","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}
The aspheric surface is a commonly used method to improve the imaging quality of the fisheye lens, but it is difficult to determine the position and initial value. Based on the wave aberration theory of the plane-symmetric optical system, a method of using an aspheric surface to design a fisheye lens is proposed, which can quickly determine the appropriate aspheric surface to improve the imaging performance. First, the wave aberration of each optical surface of the fisheye lens is calculated and its aberration characteristics are analyzed. Then, a numerical evaluation function is reported based on the aberration distribution of the fisheye lens on the image plane. According to the functional relationship between the evaluation function and the aspheric coefficient, the position of the aspheric surface and the initial value of the aspheric coefficient can be calculated. Finally, the adaptive and normalized real-coded genetic algorithm is used as the evaluation function to optimize the fisheye lens using an aspheric surface. The proposed method can provide an effective solution for designing a fisheye lens using an aspheric surface.
{"title":"Determination Position and Initial Value of Aspheric Surface for Fisheye Lens Design","authors":"Lirong Fan, Ketao Yan, Guodong Qiao, Lijun Lu, Shuyuan Gao, Huadong Zheng","doi":"10.3390/photonics10121381","DOIUrl":"https://doi.org/10.3390/photonics10121381","url":null,"abstract":"The aspheric surface is a commonly used method to improve the imaging quality of the fisheye lens, but it is difficult to determine the position and initial value. Based on the wave aberration theory of the plane-symmetric optical system, a method of using an aspheric surface to design a fisheye lens is proposed, which can quickly determine the appropriate aspheric surface to improve the imaging performance. First, the wave aberration of each optical surface of the fisheye lens is calculated and its aberration characteristics are analyzed. Then, a numerical evaluation function is reported based on the aberration distribution of the fisheye lens on the image plane. According to the functional relationship between the evaluation function and the aspheric coefficient, the position of the aspheric surface and the initial value of the aspheric coefficient can be calculated. Finally, the adaptive and normalized real-coded genetic algorithm is used as the evaluation function to optimize the fisheye lens using an aspheric surface. The proposed method can provide an effective solution for designing a fisheye lens using an aspheric surface.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"54 7","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138997348","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}
Pub Date : 2023-12-14DOI: 10.3390/photonics10121377
Shining Xu, Shuqi Zhang, J. Kirch, Cheng Liu, A. Wibowo, S. R. Tatavarti, D. Botez, L. Mawst
The surface morphology of a buffer template is an important factor in the heteroepitaxial integration of optoelectronic devices with a significant lattice mismatch. In this work, InP-based long-wave infrared (~8 µm) emitting quantum cascade lasers with active region designs lattice-matched to InP were grown on GaAs and Si substrates employing InAlGaAs step-graded metamorphic buffer layers, as a means to assess the impact of surface roughness on device performance. A room-temperature pulsed-operation lasing with a relatively good device performance was obtained on a Si template, even with a large RMS roughness of 17.1 nm over 100 µm2. Such results demonstrate that intersubband-operating devices are highly tolerant to large RMS surface roughness, even in the presence of a high residual dislocation density.
{"title":"Quantum Cascade Lasers Grown by Metalorganic Chemical Vapor Deposition on Foreign Substrates with Large Surface Roughness","authors":"Shining Xu, Shuqi Zhang, J. Kirch, Cheng Liu, A. Wibowo, S. R. Tatavarti, D. Botez, L. Mawst","doi":"10.3390/photonics10121377","DOIUrl":"https://doi.org/10.3390/photonics10121377","url":null,"abstract":"The surface morphology of a buffer template is an important factor in the heteroepitaxial integration of optoelectronic devices with a significant lattice mismatch. In this work, InP-based long-wave infrared (~8 µm) emitting quantum cascade lasers with active region designs lattice-matched to InP were grown on GaAs and Si substrates employing InAlGaAs step-graded metamorphic buffer layers, as a means to assess the impact of surface roughness on device performance. A room-temperature pulsed-operation lasing with a relatively good device performance was obtained on a Si template, even with a large RMS roughness of 17.1 nm over 100 µm2. Such results demonstrate that intersubband-operating devices are highly tolerant to large RMS surface roughness, even in the presence of a high residual dislocation density.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"31 12","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138972643","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}
Pub Date : 2023-12-14DOI: 10.3390/photonics10121373
Yuanlong Fan, Siyi An, K. A. Shore, Xiaopeng Shao
Semiconductor nano-lasers have been a topic of interest from the perspective of advancing the capabilities of photonic integration. Nano-lasers are perceived as the means to achieve improved functionality in photonic integrated circuits. The properties and performance of nano-lasers have been examined by means of simulations and laboratory measurements. Nano-lasers lend themselves to integration to form dense arrays in both one and two dimensions. In a recent work, a theoretical treatment was presented for the dynamic behaviour of stand-alone electrically pumped nano-laser arrays. In this work, the response of nano-laser arrays to direct current modulation is examined. As in previous works, attention is given to two prototype array geometries: a linear three-element linear array and an equilateral triangular array. Large one-dimensional arrays can be built by repeating this elementary linear array. Two-dimensional photonic integrated circuits can incorporate the triangular arrays studied here. Such prototypical configurations offer opportunities to tailor the modulation response of the nano-laser arrays. The principal factors which provide that capability are the coupling strengths between lasers in the arrays and the direct modulation parameters. The former are fixed at the design and manufacture stage of the array whilst the latter can be chosen. In addition, the enhancement of the spontaneous emission rate via the so-called Purcell effect in nano-lasers offers a device-specific means for accessing a range of modulation responses. Two-dimensional portraits of the regimes of differing modulation responses offer a convenient means for determining the dynamics that may be accessed by varying the laser drive current. It is shown by these means that a rich variety of modulation responses can be accessed in both linear and triangular arrays.
{"title":"Tailoring the Direct Current Modulation Response of Electrically Pumped Semiconductor Nano-Laser Arrays","authors":"Yuanlong Fan, Siyi An, K. A. Shore, Xiaopeng Shao","doi":"10.3390/photonics10121373","DOIUrl":"https://doi.org/10.3390/photonics10121373","url":null,"abstract":"Semiconductor nano-lasers have been a topic of interest from the perspective of advancing the capabilities of photonic integration. Nano-lasers are perceived as the means to achieve improved functionality in photonic integrated circuits. The properties and performance of nano-lasers have been examined by means of simulations and laboratory measurements. Nano-lasers lend themselves to integration to form dense arrays in both one and two dimensions. In a recent work, a theoretical treatment was presented for the dynamic behaviour of stand-alone electrically pumped nano-laser arrays. In this work, the response of nano-laser arrays to direct current modulation is examined. As in previous works, attention is given to two prototype array geometries: a linear three-element linear array and an equilateral triangular array. Large one-dimensional arrays can be built by repeating this elementary linear array. Two-dimensional photonic integrated circuits can incorporate the triangular arrays studied here. Such prototypical configurations offer opportunities to tailor the modulation response of the nano-laser arrays. The principal factors which provide that capability are the coupling strengths between lasers in the arrays and the direct modulation parameters. The former are fixed at the design and manufacture stage of the array whilst the latter can be chosen. In addition, the enhancement of the spontaneous emission rate via the so-called Purcell effect in nano-lasers offers a device-specific means for accessing a range of modulation responses. Two-dimensional portraits of the regimes of differing modulation responses offer a convenient means for determining the dynamics that may be accessed by varying the laser drive current. It is shown by these means that a rich variety of modulation responses can be accessed in both linear and triangular arrays.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"131 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138975479","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}
Pub Date : 2023-12-14DOI: 10.3390/photonics10121376
Wei-Chao Zhang, Lin-Heng Li, Tao Zhang
In order to improve the sensitivity and accuracy of the giant magnetostrictive material-fiber Bragg gratings’ (GMM-FBG) current sensor, in which the magnetostrictive modulator is Terfenol-D, the temperature effects on the FBG center wavelength and GMM magnetostriction coefficient are investigated to initiate an amending scheme in which temperature parameters are introduced into a GMM-FBG sensing model so as to calibrate current values. Based on electromagnetism theory, the magnetic structure is optimized in design to significantly increase the magnetic coupling efficiency and to homogenize magnetic distribution, employing finite element simulations of the electromagnetic field. The relevant experimental platform is constructed with a wavelength demodulation system. At the temperature range of 20~70 °C, response amplitudes of the current sensor are tested under various current values. The experimental results indicate that the sensitivity of the GMM-FBG current sensor decreases with the temperature increment and is also positively correlated to the target current. Through analyzing the response characteristics of the current sensor to temperature variation, a reasonable GMM-FBG sensing amelioration model with a temperature compensation coefficient is established based on a mathematical fitting method, according to which the current detecting accuracy can be increased by 4.8% while measuring 60 A current at the representative working temperature of 40 °C.
为了提高巨磁致伸缩材料-光纤布拉格光栅(GMM-FBG)电流传感器(其中的磁致伸缩调制器为Terfenol-D)的灵敏度和精确度,研究了温度对FBG中心波长和GMM磁致伸缩系数的影响,从而提出了一种修正方案,即在GMM-FBG传感模型中引入温度参数,以校准电流值。基于电磁学理论,利用电磁场的有限元模拟对磁结构进行了优化设计,以显著提高磁耦合效率并均匀磁分布。利用波长解调系统搭建了相关实验平台。在 20~70 °C 的温度范围内,测试了电流传感器在不同电流值下的响应振幅。实验结果表明,GMM-FBG 电流传感器的灵敏度随温度升高而降低,并且与目标电流呈正相关。通过分析电流传感器对温度变化的响应特性,基于数学拟合方法建立了一个合理的带有温度补偿系数的 GMM-FBG 传感改进模型,根据该模型,在 40 °C 的代表性工作温度下测量 60 A 电流时,电流检测精度可提高 4.8%。
{"title":"Structural Optimization and Temperature Compensation of GMM-FBG Fiber Current Transducer","authors":"Wei-Chao Zhang, Lin-Heng Li, Tao Zhang","doi":"10.3390/photonics10121376","DOIUrl":"https://doi.org/10.3390/photonics10121376","url":null,"abstract":"In order to improve the sensitivity and accuracy of the giant magnetostrictive material-fiber Bragg gratings’ (GMM-FBG) current sensor, in which the magnetostrictive modulator is Terfenol-D, the temperature effects on the FBG center wavelength and GMM magnetostriction coefficient are investigated to initiate an amending scheme in which temperature parameters are introduced into a GMM-FBG sensing model so as to calibrate current values. Based on electromagnetism theory, the magnetic structure is optimized in design to significantly increase the magnetic coupling efficiency and to homogenize magnetic distribution, employing finite element simulations of the electromagnetic field. The relevant experimental platform is constructed with a wavelength demodulation system. At the temperature range of 20~70 °C, response amplitudes of the current sensor are tested under various current values. The experimental results indicate that the sensitivity of the GMM-FBG current sensor decreases with the temperature increment and is also positively correlated to the target current. Through analyzing the response characteristics of the current sensor to temperature variation, a reasonable GMM-FBG sensing amelioration model with a temperature compensation coefficient is established based on a mathematical fitting method, according to which the current detecting accuracy can be increased by 4.8% while measuring 60 A current at the representative working temperature of 40 °C.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"1 4","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138972620","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}
Pub Date : 2023-12-14DOI: 10.3390/photonics10121375
A. Pushkin, F. Potemkin
The chirped pulse amplification (CPA) systems based on transition-metal-ion-doped chalcogenide crystals are promising powerful ultrafast laser sources providing access to sub-TW laser pulses in the mid-IR region, which are highly relevant for essential scientific and technological tasks, including high-field physics and attosecond science. The only way to obtain high-peak power few-cycle pulses is through efficient laser amplification, maintaining the gain bandwidth ultrabroad. In this paper, we report on the approaches for mid-IR broadband laser pulse energy scaling and the broadening of the gain bandwidth of iron-doped chalcogenide crystals. The multi-pass chirped pulse amplification in the Fe:ZnSe crystal with 100 mJ level nanosecond optical pumping provided more than 10 mJ of output energy at 4.6 μm. The broadband amplification in the Fe:ZnS crystal in the vicinity of 3.7 μm supports a gain band of more than 300 nm (FWHM). Spectral synthesis combining Fe:ZnSe and Fe:CdSe gain media allows the increase in the gain band (~500 nm (FWHM)) compared to using a single active element, thus opening the route to direct few-cycle laser pulse generation in the prospective mid-IR spectral range. The features of the nonlinear response of carbon nanotubes in the mid-IR range are investigated, including photoinduced absorption under 4.6 μm excitation. The study intends to expand the capabilities and improve the output characteristics of high-power mid-IR laser systems.
{"title":"Refining the Performance of mid-IR CPA Laser Systems Based on Fe-Doped Chalcogenides for Nonlinear Photonics","authors":"A. Pushkin, F. Potemkin","doi":"10.3390/photonics10121375","DOIUrl":"https://doi.org/10.3390/photonics10121375","url":null,"abstract":"The chirped pulse amplification (CPA) systems based on transition-metal-ion-doped chalcogenide crystals are promising powerful ultrafast laser sources providing access to sub-TW laser pulses in the mid-IR region, which are highly relevant for essential scientific and technological tasks, including high-field physics and attosecond science. The only way to obtain high-peak power few-cycle pulses is through efficient laser amplification, maintaining the gain bandwidth ultrabroad. In this paper, we report on the approaches for mid-IR broadband laser pulse energy scaling and the broadening of the gain bandwidth of iron-doped chalcogenide crystals. The multi-pass chirped pulse amplification in the Fe:ZnSe crystal with 100 mJ level nanosecond optical pumping provided more than 10 mJ of output energy at 4.6 μm. The broadband amplification in the Fe:ZnS crystal in the vicinity of 3.7 μm supports a gain band of more than 300 nm (FWHM). Spectral synthesis combining Fe:ZnSe and Fe:CdSe gain media allows the increase in the gain band (~500 nm (FWHM)) compared to using a single active element, thus opening the route to direct few-cycle laser pulse generation in the prospective mid-IR spectral range. The features of the nonlinear response of carbon nanotubes in the mid-IR range are investigated, including photoinduced absorption under 4.6 μm excitation. The study intends to expand the capabilities and improve the output characteristics of high-power mid-IR laser systems.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"22 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138972404","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}
Pub Date : 2023-12-14DOI: 10.3390/photonics10121378
Xiayin Liu, Zhiyu Cai, Xiaogang Wang, Bijun Xu
A model of a generalized pulse source, whose complex degree of temporal coherence is described by a function of the nth power difference of two instants, was constructed. As examples, we consider the generalized Gaussian and multi-Gaussian Schell-model pulse sources and study their propagation in dispersive media. It is indicated that such pulse beams present unique self-focusing, off-axis self-shifting and asymmetric self-splitting characteristics by adjusting the power exponent and phase parameters. Further, we explicitly discuss how the coherence time, summation factor as well as the dispersive coefficient significantly affect the self-focusing and self-shifting behaviors of the pulse beam. The results will benefit some applications involving pulse shaping, optical trapping and remote sensing.
我们构建了一个广义脉冲源模型,其复杂的时间相干度由两个时刻的 n 次幂差函数来描述。我们以广义高斯和多高斯谢尔模型脉冲源为例,研究了它们在色散介质中的传播。结果表明,通过调整功率指数和相位参数,这类脉冲光束会呈现出独特的自聚焦、离轴自偏移和非对称自分裂特性。此外,我们还明确讨论了相干时间、求和因子以及色散系数如何显著影响脉冲光束的自聚焦和自位移行为。这些结果将有利于一些涉及脉冲整形、光学捕获和遥感的应用。
{"title":"Propagation Properties of Generalized Schell-Model Pulse Sources in Dispersive Media","authors":"Xiayin Liu, Zhiyu Cai, Xiaogang Wang, Bijun Xu","doi":"10.3390/photonics10121378","DOIUrl":"https://doi.org/10.3390/photonics10121378","url":null,"abstract":"A model of a generalized pulse source, whose complex degree of temporal coherence is described by a function of the nth power difference of two instants, was constructed. As examples, we consider the generalized Gaussian and multi-Gaussian Schell-model pulse sources and study their propagation in dispersive media. It is indicated that such pulse beams present unique self-focusing, off-axis self-shifting and asymmetric self-splitting characteristics by adjusting the power exponent and phase parameters. Further, we explicitly discuss how the coherence time, summation factor as well as the dispersive coefficient significantly affect the self-focusing and self-shifting behaviors of the pulse beam. The results will benefit some applications involving pulse shaping, optical trapping and remote sensing.","PeriodicalId":20154,"journal":{"name":"Photonics","volume":"13 3","pages":""},"PeriodicalIF":2.4,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138972562","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}