Research and Design of Photoelectric Converter for Quantum Gravimeter

In the control system of a quantum gravimeter, the optical signal containing phase information is weak and usually at the nV level. This situation puts forward high requirements for the measurement performance of the system. As the coupling input component of the measurement system, the noise level of the preamplifier has a dramatic influence on the noise performance. In this paper, the input current signal is provided by the photodiode. According to the photodiode output characteristics, we design three preamplifiers with different gain and bandwidth, which is verified by the optical system. Under the condition of meeting the design requirements, the noise performance is compared with the common commercial detector Model 2307. The results show that the noise performance of the photoelectric converter designed in this paper is about 1.5 times that of model 2307.