实现量子信息传输的一种新方案

就多粒子(N>3)构成的自旋链传输单态信息进行了研究,提出了实现量子信息传输的一种新方案.采取只考虑近邻相互作用的经过修正的Heisenberg XX模型,当λt较小时,可以把演化算符作一个简单的泰勒展开,然后根据演化算符的具体作用来决定展开项中指数m只能取N-1,就可以得到自旋链上的一端单信息量子态演化到另一端的概率幅的具体形式:|F(t)|=|(-iλt/2)|N-1=1,那么只要选取适当的时间t,就使得单态量子信息在此自旋链上得以完备传输.

A New Scheme on Realizing Quantum Information Transfer

The single state information transfer was studied and a new scheme was introduced. The Hamiltonian, we adopt,is modified Heisenberg XX model which describes a nearest-neighbor interaction in spin chain. When λt is relative small, the evolution operator can be made Talor spread and then we can determine that the exponential of spreading item is taken N-1,where N is the number of the lattice in spin chain. We can obtain the probability amplitude of single state information transfer from one side to the other: |F(t)|=|(-iλt/2)|N-=1. Then the single state information can be perfectly transferred in spin chain as long as we take the proper time t.