Studies On Miniaturized Atom Interferometers And Their Applications In Precision Measurement

Atom interferometers have become widely used and flexible tools for a range of applications in fundamental and applied physics,such as inertial sensing,fundamental constants measurement and equivalence principle test.On the one hand,large-scale and lab-based atom interferometer paves the way for high accuracy geophysical or even astronomical measurement.On the other hand,to make atom interferometer miniaturized and portable is also significant for field measurement in local gravity,hydrological detection and resource prospecting.This dissertation is based on the two miniaturized atom interferometers which I have worked for as the main student in charge during the Ph.D.The full text contains the conceptual design,the experimental setup and the measurement results of both project.Start with laser cooling techniques,in the first chapter,development of gravity detection and the comparison between different detection methods are briefly introduced,which put the highlight on the advantages of atom interferometer method.Also,the state of the art atom interferometers is listed for a complete macro concept map.Chapter 2 is the theoretical analysis on atom interferometers,which including the theory of atom cooling,interaction between atom and light,how the manipulations on atoms by Raman pulse happened and also why the polarization of the Raman light is so important.And based on these,a specific calculation on the phase accumulation in a Mach-Zehnder interferometer is conducted at last.Chapter 3 and Chapter 4 are for the experimental constructions and characteristics of the miniaturized atomic fountain interferometer and miniaturized pyramidal atom interferometer,respectively.The introductions mainly focus on vacuum system,optical system,frequency locking and control system.Whereas,Chapter 5 and Chapter 6 demonstrate the corresponding measurement results for the two atom interferometers.As for the miniaturized atomic fountain interferometer,we achieved the capture of cold atoms,height controllable atomic fountain,state selection and the interference under both Doppler insensitive and sensitive Raman configuration,with the results and sensitivity of the absolute gravity measurement obtained.The sensitivity of the gravity measurement ?g/g is 4.5×10-7.As for the miniaturized pyramidal atom interferometer,we also achieved the capture of cold atoms,state selection,microwave manipulation and the interference under both Doppler insensitive and sensitive Raman configuration,and due to the specialty of the pyramidal mirror,we not only operate absolute gravity measurement,but also the measurement of inclination and rotation,the sensitivities of the three measurement are 6 μm/s²/Hz^1/2,4 μrad/Hz^1/2 and 170 μrad/s,respectively.In the last chapter,the main experimental results are summarized for both atom interferometers.In terms of their own characteristics,the solutions to the problems and the suggestions for the next step are proposed.