Research On Few-Body Correlation And Pump-Probe Response In A Hybrid Optomechanical System

In recent years,with the development and wide application of laser cooling and trapping techniques,coherent controllable ultracold Rydberg atoms have attracted more and more attention in the field of quantum information and quantum optics.There are some novel physics in the Rydberg atom,the most representative of which is the dipole blockade effect caused by the strong long-range dipole-dipole interaction between the Rydberg atoms.Quantum information processing and quantum multi-body simulation can be realized with Rydberg atoms,and the Rydberg atom is deemed to be the most attractive physical system to be studied at present.On the other hand,maturity and progress of micro and nanotechnology have really made the study of quantum optomechanics flourish.Nanotechnology has made possible the manufacture of micro and high quality mechanical oscillators.This kind of reflex oscillator can be used as a optomechanical device of inductive light radiation pressure(usually negligible).Therefore,all kinds of optomechanical systems have a good prospect in exploring innovative quantum behavior effectively.Because of its inherent classical and quantum properties,Quantum optomechanics opens the way for ultra-precision measurement.It is worth noting that a lot of important research work has been carried out on these fields.This paper mainly be focused on the above two different fields.The purpose of this paper is to conduct some preliminary work on the combination of the two fields.On the one hand,we study the two-body entanglement in the few-body Rydberg atomic system.The relation between the elicitation probability of Rydberg atom and quantum entanglement under dipole blockade and anti-blockade regimes are all discussed.On the other hand,the pump-probe response of a two-level atomic ensemble system is studied.To combine the two areas,That is,the Rydberg atom is trapped in an optomechanical cavity,and the influence of quantum correlation on the pump-probe photomechanical behavior can be investigated.This part of the study is not considered here.There are five chapters in this paper,the third and fourth chapters are our main research work.The content is arranged as follows:In the first chapter,the background,structure and content of the research on Rydberg atom and quantum optomechanics are introduced.In the second chapter,the basic theories which are closely related to our research are given,including the input and output relation of the quantized optical cavity,the Heisenberg-Langevin equation,Rydberg atom and their interaction.In chapter 3,entanglement in a dilute Rydberg atomic gas is studied,and the relation between steady and dynamical coherent excitation and two-body entanglement are discussed by using a four-body atomic system.In chapter 4,we study the excitation behavior of atoms without any approximate means given the coupling constants of atomic ensemble and cavity mode,and give the physical explanation of the optotomechanical response of the system.Finally,we summarize the research results of this paper.