Design And Implementation Of Magnetic Field Sensor Based On Cavity Optomechanical System

With the development of science and technology,people’s demand for the accuracy of measurement equipment is gradually increasing.Magnetic field sensors,as an important part of measurement equipment,have wide applications in industries such as information industry,industrial automation,transportation,electronic technology,office equipment,home appliances,medical equipment,etc.However,the existing traditional magnetic field sensors are gradually unable to meet people’s needs,mainly due to problems such as large volume,poor electromagnetic interference resistance,and difficulty in integrating with current CMOS circuits.Therefore,developing a high-precision magnetic field sensor has important research value.This article analyzes the advantages and disadvantages of existing magnetic field sensors,as well as the advantages of cavity optical force systems in the field of magnetic field sensors,Three Lorentz force magnetic field sensor structures based on cavity optical force systems were designed,and one of the sensors was processed and tested for its performance.The main research content and achievements of this thesis are as follows:1.A design scheme for Lorentz force magnetic field sensor based on cavity optical force structure is proposed,utilizing the efficient optomechanical energy coupling characteristics of cavity optical mechanical structure;Use Simulink simulation software to verify the relationship between the theoretical parameters of the magnetic field sensor.Through simulation analysis,it is found that the designed magnetic field sensor has an input laser intensity of 199μW,its magnetic field detection sensitivity is 7.9μT/Hz.The COMSOL simulation software is used to simulate and design the structure and parameters of the magnetic field sensor,and three kinds of magnetic field sensors are designed,namely,the straight mechanical vibration Substructure,the long straight small mass mechanical vibration Substructure,and the inner and outer nested mechanical vibration Substructure.The stability,optical resonance characteristics,mechanical resonance characteristics,and power consumption of the designed magnetic field sensor structure were simulated and analyzed.The sensitivity and resolution characteristics were theoretically analyzed.2.On the basis of completing the simulation design,this article introduces the problems encountered during chip processing and their solutions.The initial version of the magnetic field sensor chip was processed and prepared,and a performance testing platform was built.The stability,optical resonance characteristics,mechanical resonance characteristics,and siganl stability of the magnetic field sensor chip were tested and analyzed.Through in-depth research on cavity optical force systems and the design of new magnetic field sensors in this article,it is helpful to promote the application of this technology in precise measurement and other fields,which is of great significance for scientific development and social progress.