Study Of Phonon Blocking Effects In Hybrid Quantum Systems

Cavity quantum electrodynamics(QED)provides a pure and coherent environment,which helps to understand the fundamental behaviors of the interaction between matter and field at single particle level.Compared with the CQED,the superconducting circuit quantum electrodynamics system has the advantages of easily achieving strong coupling and long interaction time between cavity modes and atoms.The hybrid quantum system composed of surface acoustic waves and superconducting quantum circuits combines the advantages of cavity QED and superconducting circuit QED.It has attracted extensive attention,leading to the emergence of so-called "circuit quantum acoustodynamics",which can help researchers to manipulate a single phonon and provide a variety of methods for quantum information processing based on phonons.In this thesis,we suggest a hybrid quantum system composed of surface acoustic waves(SAW)and superconducting quantum circuits,and investigate the phonon blockade and its applications.The research results are as follows:We propose an effective N-type artificial atom-like system combining the SAW resonator and superconducting circuit QED,and investigate the phonon-phonon interaction.Two cases are considered for phonon blockade.The first SAW phonon blockade results from a large self-Kerr nonlinearity,which created by the strong interaction between the superconducting qubit and the vacuum field in a microwave resonator.In the second case,the vacuum-qubit coupling creates a bound state for a propagating SAW,leading to phonon blockade.