实现双盖格-米勒(Geiger-Müller,GM)计数管量程扩展测量的关键是双GM计数管量程切换控制技术,该技术可使探测器自动选择合适量程的GM计数管进行测量。但是由于两种不同测量量程的GM计数管存在性能差异,传统的将测量量程分成两个区域的方法会导致双GM计数管在量程交叠区域内线性拟合度较低。为了提高双GM计数管在测量量程交叠区域内的线性度,提出了一种量程控制测量方法。该方法将测量范围划分为低量程、中量程以及高量程三个区间,并且还可在三个测量量程之间进行快速自动切换,其中在中量程测量中,分别将两个GM计数管获得的数据进行加权处理。采用241Am源和60Co源进行双GM计数管探测器电路测试,初步测试结果表明:设计的双GM计数管探测器可实现在三个测量量程区间内快速自动切换。同时,双GM计数管在剂量率交叠区域1 000~10 000 μGy·h-1中的线性拟合度得到改进,使得在251~25 130 μGy·h-1的测试范围内,双GM计数管的测量线性度提高至0.999 1,有效地提高了双GM计数管的整体测量线性度。
双GM计数管 量程切换 交叠区域 Dual Geiger Miller counter tubes Range switch Overlapping region
1 江西师范大学江西省光电子与通信重点实验室,江西 南昌 330022
2 上海交通大学平湖智能光电研究院,浙江 平湖314200
设计并制备了一种基于树形结构的1×8硅基热光开关,该热光开关由1个2×2和6个1×2马赫-曾德尔干涉仪的基本单元结构组成。该1×8硅基热光开关采用与互补金属氧化物半导体兼容的工艺制造。通过氮化钛加热器来改变波导的温度,利用硅的热光效应实现光开关功能。实验结果表明:在1550 nm工作波长下,该热光开关的平均片上插入损耗约为1.1 dB;所有输出端口的串扰都小于-23.6 dB;开关响应时间小于60 μs。
集成光学 硅基开关 马赫-曾德尔干涉仪 热光开关
强激光与粒子束
2024, 36(2): 025004
强激光与粒子束
2024, 36(2): 025019
强激光与粒子束
2024, 36(2): 025009
中国矿业大学信息与控制工程学院,江苏 徐州 221116
提出了一种基于电磁诱导透明(EIT)的多功能偏振无关超表面,其基础结构由1个金属十字结构和4个方环结构组成,并引入了可调控材料硅(Si)以及二氧化钒(VO2),以实现温光双控。利用模拟计算和理论模型分析得到了基础结构作为双明模间接耦合形成EIT透明窗口的结论。由于EIT以及可调控材料的特性,本设计可以在分子传感、可控慢光以及双通道温光双控开关等领域实现应用,并且具有优异的性能。该结构对蔗糖溶液的传感灵敏度为97.6 GHz/(kg/m3),在分子检测领域展示出了巨大潜力。该结构实现了对慢光效应的可选择控制。依据EIT的作用机理,提出了利用可调控材料改变结构谐振进而控制电磁响应的设计思路,并实现了一种双通道温光双控开关,为今后的EIT超表面设计提供了参考。
表面光学 超表面 可调控材料 分子传感 慢光效应 温光双控开关
Author Affiliations
Abstract
1 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences (CAS), Xi’an 710119, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
3 College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Silicon waveguides typically exhibit optical anisotropy, which leads to polarization correlation and single-polarization operations. This consequently creates a demand for polarization-control devices. This paper introduces a CMOS-compatible O-band reconfigurable TE/TM polarization rotator comprising two symmetrical polarization rotator–splitters and phase shifters. This configuration enables dynamic conversion of any linear polarization to its quadratic equivalent. Experimental results indicate that the reconfigurable polarization rotator exhibits an insertion loss of less than 1.5 dB. Furthermore, the bandwidth for a polarization extinction ratio beyond 15 dB exceeds 60 nm.
silicon-based optoelectronics polarization rotation polarization switch Chinese Optics Letters
2024, 22(1): 011303
Author Affiliations
Abstract
1 Faculty of Electrical Engineering and Computer Science, Ningbo University, Ningbo 315211, China
2 College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou 325035, China
3 College of Science and Technology, Ningbo University, Ningbo 315300, China
4 Laboratory of Infrared Materials and Devices, The Research Institute of Advanced Technologies, Ningbo University, Ningbo 315211, China
5 Department of Information Science and Electronics Engineering and Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China
A flexible-grid mode- and wavelength-selective switch which comprises counter-tapered couplers and silicon microring resonators has been proposed, optimized, and demonstrated experimentally in this work. By carefully thermally tuning phase shifters and silicon microring resonators, mode and wavelength signals can be independently and flexibly conveyed to any one of the output ports, and different bandwidths can be generated as desired. The particle swarm optimization algorithm and finite difference time-domain method are employed to optimize structural parameters of the two-mode (de)multiplexer and crossing waveguide. The bandwidth-tunable wavelength-selective optical router composed of 12 microring resonators is studied by taking advantage of the transfer matrix method. Measurement results show that, for the fabricated module, cross talk less than , an extinction ratio larger than 17.41 dB, an in-band ripple lower than 0.79 dB, and a 3-dB bandwidth changing from 0.38 to 1.05 nm are obtained, as the wavelength-channel spacing is 0.40 nm. The corresponding response time is measured to be 13.64 µs.
integrated optics optical waveguide mode- and wavelength-selective switch Chinese Optics Letters
2024, 22(1): 011301
1 重庆邮电大学 光电工程学院/国际半导体学院, 重庆 400065
2 中国电子科技集团公司第二十四研究所, 重庆 400060
在流水线模数转换器(Pipeline ADC)电路中, 栅压自举开关中的非线性电容会对开关管的导通电阻产生直接的影响, 导致采样非线性。设计了一种三路径的高线性度栅压自举开关, 采用三个自举电容, 分别构成两条主路径和一条辅助路径, 使得输入信号在通过两条主路径传输到开关管栅端时加快栅端电压的建立, 同时利用辅助路径驱动非线性电容, 减少电路中非线性电容对采样电路线性度的影响, 从而增强信号驱动能力, 提高整体电路的精度。本文设计的栅压自举开关应用于14 bit 500 MHz流水线ADC的采样保持电路中。采用TSMC 28 nm CMOS工艺进行电路设计。仿真结果表明, 在输入频率为249 MHz, 采样频率为500 MHz的条件下, 该栅压自举开关的信噪比(SNDR)达到92.85 dB, 无杂散动态范围(SFDR)达到110.98 dB。
栅压自举开关 采样保持电路 非线性电容 主路径 辅助路径 gate voltage bootstrap switch sample and hold circuit nonlinear capacitance main path auxiliary path
1 重庆西南集成电路设计有限责任公司, 重庆 401332
2 安徽大学 集成电路学院, 合肥 230601
3 中国电子科技集团公司第二十四研究所, 重庆 400060
基于013 μm CMOS SOI工艺, 设计并实现了一种100 MHz~12 GHz高功率SPDT射频开关。该射频开关为吸收式射频开关, 开关支路为串并联的拓扑结构。采用负压偏置设计, 减小了插入损耗, 提高了隔离度。采用多级开关管堆叠设计, 提高了开关的输入1 dB 压缩点。测试结果表明, 在100 MHz~12 GHz频率范围内, 该射频开关插入损耗小于15 dB, 隔离度大于31 dB, 输入1 dB 压缩点大于40 dBm。芯片尺寸为11 mm ×11 mm。
高功率 高隔离度 射频开关 high power high isolation RF switch SOI SOI