弱耦合近似条件下量子位的消相干

DECOHERENCE OF QUANTUM BIT IN THE WEAK-COUPLING LIMIT

利用子动力学方法讨论了Liouville空间中弱耦合近似条件下量子位的消相干问题,给出了N个量子位的非Markovian过程演化动力学方程和不同时间阶数近似条件下量子位消相干速率,提出了弱耦合条件下非Markovian过程中量子位无消相干一般判据以及投影子空间中量子计算的纠错方法.

The decoherence of the quantum bit is studied in the approximation of weak coupling in the Liouville space. The dynamic equation of N quantum bits is given in the weakly coupling limits and under the non-Markovian approximation. The rate of decoherence is given in the approximation of different time order. Based on the above results, the general form of criterion for decoherence-free states is proposed. Also a new method for quantum correction is proposed from the non-Markovian dynamic equation in the weak coupling limit.