Noise Characteristic Analysis And Experimental Research Of Balanced Homodyne Detector

With the rapid development of science and technology,the precision and accuracy of optical precision measurement,optical communication and optical information processing have reached a higher and higher level.In the measurement and processing of optical signal,although the influence of the classic error source can be deleted with an effective method,but the quantum noise still exists,and the presence of the noise is fundamentally constrained the accuracy of the optical precision measurement and the optical communication.Therefore,how to reduce the impact of quantum noise on measurement is one of the hot topics of scientific and technological workers.The balanced homodyne detection is the best way to measure the quantum noise of the light field.This method can directly characterize the orthogonal noise of the signal light,and can effectively reduce the influence of the classical noise on the measurement,and can effectively amplify the weak signal,so as to greatly improve the signal-to-noise ratio of the detector.In this thesis,the detection principle,circuit structure and measuring performance of balanced homodyne detection are introduced firstly,and the basic principles and performance parameters of photoelectric detection devices and operational amplifiers are also introduced.The noise characteristics of balanced homodyne detection with transimpedance amplifier circuit are analyzed emphatically,and the formulas of gain spectrum,electronic noise,shot noise and signal-to-noise ratio are calculated theoretically.The key factors affecting the signal-to-noise ratio and bandwidth of the detector are analyzed,and the selection standards of photoelectric detection devices and operational amplifiers are given.Secondly,the noise model of the balanced homodyne detection is given by using the simulation software and the model of each part of noise source.Finally,the experimental circuit diagram is designed,the PCB board is made,and the final development of the bandwidth of 10 MHz,signalto-noise ratio of 14 d B,common mode rejection ratio of 43 d B balanced homodyne detection.It satisfies the requirements of the detector in the quantum optical experiment well,and finds out the factors that the bandwidth and signal-to-noise ratio of the balanced homodyne detection cannot be improved by combining the experimental data from theoretical calculation and software simulation.