The Study On The Dynamics Of Quantum Correlations And Weak Force Sensing In Hybrid Optomechanical Systems

Quantum information processing presents several charming properties since it employs quantum coherence.During several decades,significant efforts have been undertaken to multi-particle systems such as quantum entanglement,quantum correlation and quantum steering as a fundamental feature of quantum coherence.In particular,quantum entanglement is one of the most fascinating non-classical physical properties of multi-particle systems and it has brought us many new insights into computer science,quantum physics,quantum information,and many other fields.Preparation and quantifying of continuous variables(CV)correlations are just an advantage in the field of quantum optics and quantum information.Nowadays,the research field of cavity optomechanical system is at the heart of widespread theoretical and experimental investigations and remarkable progress towards the testing of quantum mechanics and provides many useful tools for quantum information processing.On the other hand,an optomechanical system is promising for performing high-precision measurements,ultra-sensitive force detection,two-mode squeezed states,Micro-to-Macro entanglement,and optomechanical storage.Besides,the hybrid optomechanical system can be used as a quantum device to realize the dynamical quantum steering,to cool the mechanical oscillator to its ground state,to serve as the quantum sensor,and to enhance the quantum information and leads to the global quantum int,ernet.All these novel phenomena become fascinating research topics and potent.ial platforms to study the optomechanical system.In this dissertat,ion,we mainly focus on the dynamics of quant.um correlat.ions and weak force sensing in hybrid opt,omechanical systems.The dissertation is structured as follows.In chapter 1,we first briefly introduce the development of quantum theory as well as the background of cavity optomechanical systems.In chapter 2,we bring in the community to the basic knowledge of quantum phenomena,including the conceptual structures of quantum entanglement,quantum correlations and research methods of open quantum systems.Finally,we give an extensive introduction and fundamental tools of coherent quantum noise cancellation for weak force measurements in an optomechanical system.In chapter 3,we have studied the dynamics of quantum correlations in different systems.In t he first case.,we consider the dynamics of the quant.um correlation of four-qubit systems.We have quantified this kind of dynamics by using consonance and concurrence as a measure-ment of quantum correlation and entanglement,respectively.In the second case,we examine the dynamics of the quantum correlation of continuous variable(CV)system.In chapt.er 4,we also investigate quantum correlation and steering in optomechanical systems.In t.he first case,we analytically discuss the C.V correlation of txwo coupled op-tomechanical systems.We find that the correlation always exists bet.ween two optical fields,and two-oscillators.In the second case,the dynamical quantum steering in a pulsed hybrid electro-optomechanical system is investigated.Our result shows that there is the possibil-ity of bipartite entanglement,one-way steering,two-way steering,and collective tripartite steering between different output modes.In chapter 5,we also study the weak force sensing based on pre-cooling processes and coherent quantum noise cancellation in a hybrid optomechanical system.We have shown that these processes can significantly improve optomechanical force sensing.Moreover,the coherent,quantum noise cancellation which allows continuous and broadband sensing of weak forces beyond the standard quantum limit,and setting up the system in the resolved sideband regime can lead to optimizing the cooling processes in the hybrid system.In chapter 6,we give conclusions and future work of the dissertation.