The Implementation Of Quantum?statetransfer And Quantum Entanglement In A Dissipative Optical Cavity

Fast and accurate preparation and manipulation of quantum states is a hot topic in the field of quantum information processing and quantum computing,which has potential application value in quantum information,quantum communication,quantum measurement and quantum sensing.As an important resource,dissipation plays an active role in the preparation of entangled states and the transmission of quantum states,which is also of great significance to the development of quantum information.Compared with other physical systems,cavity quantum electrodynamics system(cavity QED)is an important platform for realizing various quantum state manipulations because it can store information by atoms and transmit information by photons.Coupled cavity QED array system has the advantage of scalability and can provide good technical support for the development of quantum information.In recent years,a lot of research work has emerged based on coupling cavity system,among which the realization of quantum state control has always been a popular research content.Quantum computation,quantum communication and quantum encryption are closely related to the control of quantum state.In this paper,the dissipative optical cavity is used to realize the quantum state transmission scheme.The main research results are as follows:First,we have successfully implemented a unidirectional quantum state transmission scheme in a dissipative coupled cavity array.Quantum state transmission plays an important role in quantum information processing and many achievements have been made theoretically and experimentally.We use the dissipation method to assist the unidirectional quantum state transmission and transfer any quantum state from the "transmitting" end to the "receiving" end.The optical cavity dissipation can keep the quantum state stable at the receiving end.At this point,the target state becomes the stable state of the whole process and does not depend on time.Furthermore,the spontaneous emission of atoms is significantly inhibited by adiabatic elimination of the excited state.At the same time,the experimental feasibility of the scheme is analyzed.The results show that the fidelity of the transmitted state at the receiving end can reach more than 98%.Secondly,we systematically study the feasibility of generating three-dimensional entangled states from two four level atoms in a coupled cavity array using dissipation.Using adiabatic elimination,we can simplify the coupling model of two single-mode cavities to a single-mode cavity model.Usually,quantum dissipation will hinder the preparation of entangled states,but in this scheme,we can make use of the dissipation method to prepare entangled states very effectively,which transforms the noise source into a beneficial resource.The numerical simulation verifies the effective operator theory,and it is in good agreement with the main equation under the given parameter.Through ground state coupling of classical field and spontaneous emission of atoms,we can obtain stable and high fidelity entangled states in different initial states.