高阶模光学小位移测量系统中信号光功率对最小可测位移量的影响  

Influence of Signal Optical Power on Minimum Measurable Displacement in High⁃Order ModeOptical Small Displacement Measurement System

作　　者：赖永浪 张超霞 成亚哲 刘喆 张静[1,2,3] 刘奎 孙恒信 杨荣国 Lai Yonglang;Zhang Chaoxia;Cheng Yazhe;Liu Zhe;Zhang Jing;Liu Kui;Sun Hengxin;Yang Rongguo(College of Physics and Electronic Engineering,Shanxi University,Taiyuan 030006,Shanxi,China;State Key Laboratory of Quantum Optics and Quantum Optics Devices,Taiyuan 030006,Shanxi,China;Institute of OptoElectronics,Shanxi University,Taiyuan 030006,Shanxi,China;Center of Information Management and Development,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China)

机构地区：[1]山西大学物理电子工程学院,山西太原030006 [2]量子光学与光量子器件国家重点实验室,山西太原030006 [3]山西大学光电研究所,山西太原030006 [4]太原理工大学信息化管理与建设中心,山西太原030024

出　　处：《中国激光》2023年第5期185-191,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(11874248,11874249,62027821)。

摘　　要：实验搭建了高阶模光学小位移测量系统。利用高阶模作为本底光的平衡零拍系统进行测量,在600 kHz~3 MHz频率段,以200 kHz为间隔,分别测量了13个频率处的小位移,并给出了相应的最小可测位移量。在不同2 MHz信号光功率条件下,研究了压电陶瓷驱动电压、噪声功率谱、信噪比以及最小可测位移量之间的关系,并利用90μW的信号光获得了1.76×10^(-10) m的最小可测位移量。该结果为基于光束横向位移测量系统进一步减小测量范围的下限提供了理论与实验依据。Objective Measurement has always been important in science;the improvement of precision measurement technology can facilitate the exploration of the micro world and has great significance in daily life and production activities.Atomic clocks,for example,can accurately measure time and frequency,which is crucial for coordinating information systems.Similarly,the accurate measurement of displacement is important.For example,the measurement of beam lateral displacement can be used in many fields,such as in atomic force microscopy,optical imaging,space satellite position stability,optical tweezers,and biological measurements.In displacement measurement,noise interference from mechanical vibration,beam pointing,laser intensity,and other factors is inevitable.These noises affect measurement results and increase the difficulty of measurement.However,most of the noise is concentrated at low frequencies.To improve the signaltonoise ratio of beam lateral displacement measurement,we test the influence of signal optical power on beam lateral displacement measurement.We prove that increasing the power of the light signal can improve the signaltonoise ratio of beam lateral displacement measurement and reduce the minimum measurable displacement.Methods Figure 3 shows the experimental devices.An allsolidstate singlefrequency laser outputs infrared light with a wavelength of 1064 nm through a Faraday optical isolator and phase modulator.A beam splitter then divides the infrared light into two parts.One part of the laser generates a TEM00 mode signal through mode conversion cavity 2(MC2).The other part uses mode conversion cavity 1(MC1)to generate the TEM00 mode required for interference adjustment or TEM10 mode as background light.MC1 and MC2 are locked by two sets of electronic servo systems.Before the displacement measurement,the TEM00 mode is outputted by MC1,and its power is adjusted to the same level as that of the signal light.Simultaneously,a highvoltage amplifier is used to drive a piezoelectric ceramic 1(PZT1)to control

关 键 词：量子光学 小位移测量 高阶横模 信号光功率 信噪比 

分 类 号：O436[机械工程—光学工程]