Teleportation Based On Four-mode Coherent Entangled State

Many scholars have conducted researches and by combining quantum mechanics and information science, they put forwarded a new subject-- quantum information theory. With decades of study and improvement, the theory of quantum mechanics has expanded into a larger scope, which makes it a favor in the research field. As an important part of quantum information theory, quantum communication has quantum teleportation as its critical part. Quantum teleportation, if it shall be fully utilized, will bring a new tide of development in the field of quantum information and quantum calculation. With the progress of society, people’s demand for information is also increasing. In this world of information explosion, it is very necessary to promote the development of information science and technology.After we study the basic concepts of quantum communication and go over its developmental phases, we will have a deeper research on teleportation. This thesis suggests using four-mode entangled coherent state as a quantum channel, and three-mode coherent superposition state as the quantum information to be transmitted which will be analyzed by a linear optical system consisting of a beam splitter and a phase shifter, and measured by odd and even relevant state. The results will be told through the classical channel so the operator will choose a more proper way to recover the transferred quantum information. At the same time, the fidelity and transmission probability of quantum teleportation will be computed. This project will achieve an almost perfect probability of successful implementation, and the fidelity is almost 1. To sum up, its effect is very obvious.