Research On Ouantum Nondestructive Measurement Based On Cold Atoms

In the precision measurement based on cold atom ensemble,as the accuracy of measurement is getting higher and higher,we need to input the correlative atoms to break through the standard quantum limit in measurement.Methods of producing these correlative atoms also emerge in endlessly.Quantum non-destructive measurement,as a method to generate atomic spin squeezed states,has been extensively studied in the past 20 years.This paper introduces the author's work on this research.In the first chapter,the research background of quantum non-destructive measurement and spin squeezed state generation is introduced,including the basic principle,development context and development status.In the second chapter,the characteristics of studying the interaction between light and atoms based on cold atomic ensemble is introduced.After a brief introduction of the basic theory of the interaction between light and atoms,the technical path of quantum nondestructive measurement to produce spin squeezed states is introduced.In the third chapter,we realized the preparation and storage methods of cold atom samples and related experimental techniques.First,the primary cooled atoms are trapped in the magneto-optical trap,and then the atoms are further cooled to a low temperature of less than 10?K or so.At the same time,the cooled atoms are loaded into the prepared far-detuned dipole trap to store the atoms for about 1s,thus preparing the atomic samples for the next detection.In the fourth chapter,the Mach-Zehnder interferometer,a tool for measuring the interaction between light and atoms,is theoretically analyzed,and the locking and noise suppression of the Mach-Zehnder interferometer are realized.Finally,in chapter 5,quantum non-destructive measurement of atomic properties in the well is introduced to realize real-time and stable monitoring of parameters in the well.In the last chapter,we summarize the results of this work and make a prospect for the next experiment.