Quantum Measurement,Teleportation And Quantum Logic Circuit

Teleportation is important in the field of quantum communication. Because of it's special transmission mechanics and potential value in future, many researchers have paid more attention on it. Quantum entanglement, theory of non-locality and non-clone law play the important roles in teleportation. This thesis investigates the basis theory of teleportation of unknown arbitrary quantum states and the quantum logic circuit by absorbed the pioneers' production. Through the non-locality of the quantum entanglement, teleportation schemes of arbitrary three-particle and multi-particle states are proposed. Their quantum logic circuits are also given. Then we vista a scheme for many-particle unknown states teleportation. At the end, we introduced some means in experimentations to realize quantum gates and quantum logic circuits.The quantum teleportation means when one teleports the unknown quantum state|ψ〉 of a particle at palace A to another one at place at B , enable another particle to be thequantum state of |ψ〉 and the original particle remain at the primary place. Due to theuncertain principal of quantum mechanics, one cannot extract all information from the original quantum state exactly. Therefore , one divides all information of the original quantum state into two parts: general information and quantum information . A classical channel informs general information and quantum channel informs quantum information. According to these messages, one can configure all information of the original quantum state at place B.Teleportation of an unknown quantum state includes three processes: preparing entangled EPR states, performing joint Bell state measurement on the particle that will be teleported and one particle of the EPR state, and then performing a unitary transformation on the second particle of the EPR state. A scheme for teleporting an arbitrary n-particle state is proposed. Alice performs a Bell state measurement on her particles n times. She informs Bob the results of the measurements through classical channels. Then Bob...