The Design Of An All-optical Semi-vector Atomic Magnetometer

All-optical semi-vector atomic magnetometer is a kind of high sensitive all-optical cesium atomic magnetometer device.Atomic magnetometer has important meaning and research value.Atomic magnetometer was regarded as one of the top ten emerging technologies in Technology Review magazine.The principle of atomic magnetometer is based on Cs atomic Lamor procession frequency is proportional to the physical properties of the external magnetic field intensity.The implementation of Cs atomic is controlled by means of frequency stabilization of894.6nm laser intensity modulation and then produce atomic polarization and Lamor procession.At the same time,another laser whose working frequency is 852.3nm tested the polarized atoms procession frequency.So we can realize the precise measurement of the external magnetic field.Atomic magnetometers have a great number of applications.In the field of medicine,doctors can quickly find patients lesions by detecting the distribution of the weak magnetic field in the brains.In industry,in order to realize the nondestructive flaw detection,workers can observe the magnetic field distribution on the surface of the metals in auto production assembly line to make sure the surface of the metal is smooth.In the field of geological exploration,the location of the well and mineral resources can be fast and accurately explored by magnetometer.In the military field,magnetometers play an important role on the satellite space detection,deep-water submarine positioning,magnetic fuze and geomagnetic navigation technology.Traditional magnetometer is aimed at the value of the magnetic field measurement,and measuring level is very accurate.A free spin exchange?SERF?highest potassium atomic magnetometer measurement sensitivity can be achieved as0.54fT/Hz¹².At present,there are many kinds of magnetometers,such as flux-gate magnetometer based on Faraday's law of electromagnetic.The proton magnetometer using proton procession in the magnetic field.Although these kinds of magnetometers have reached a certain requirement on measuring precision and sensitivity,the traditional magnetometer is known in the magnetic field direction of single axis measurement.It has some limitations to the complex environment and non-standard magnetic field measurement.The aim of the present invention is based on the all-optical cesium atomic magnetometer experiment system to create a vector field model.Then we use the device to measure the vector field model.The all-optical semi-vector atomic magnetometer not only has traditional cesium atomic magnetometer high sensitivity and can also judge the direction of the magnetic field.The study is carried on from four aspects.At first,the background of the magnetometers is briefly introduced.Then this paper introduces the atomic magnetometer development level at home and abroad and the atomic magnetometer development trend in the future.At last we put forward this topic research content,purpose,significance and structure arrangement.Next,we describe the work principle of the magnetometer,based on this topic research the Cs atoms under the condition of the external magnetic field with the interaction of light.The characteristics of the Cs atoms,Zeeman effect of Lamor procession and alkali metal atoms in Lamor procession and Spin relaxation techniques are described briefly.We design the overall scheme of Cesium atomic magnetometer and the specific physical system structure.The physical system of Cs atomic magnetometer is built successfully.Then,we studied the technology of laser frequency stabilization.In the design of all-optical semi-vector atomic magnetometer,the steady pump and probe beam is needed.This part introduces three kinds of laser frequency stabilization technology.Saturated absorption spectrum technology;Free-Doppler spectral technology and DAVLL.Saturated absorption spectrum technology is used in this study.So the basic principle and experimental study of saturated absorption spectrum technique is described in detail in this paper.Finally,we set up the semi-vector model of all-optical Cs atomic magnetometer.We derived the mathematical relationship between?and?of the model.Theoretical simulation and experimental research is carried out to get a highly sensitive all-optical semi-vector atomic magnetometer.Then we compare the theoretical value and experimental data,analysis the performance of the light half-vector atomic magnetometer.