不同自旋量子相干的密度矩阵计算

Density Matrix Calculation of Quantum Coherence of Different Spins

本文利用密度矩阵的对称共轭性,提出一个在弱相互作用下,方便地计算量子相干的方法。首先推导出纯体系的各种公式,然后计算不同自旋四种混合体系的各种量子相干。获得了它们的数目的比值以及它们的总和。推导出混合体系的各种公式。除理论计算外,还扼要地讨论这一研究结果的意义。

In this paper, a calculating method of quantum coherence under weak interactionwas advanced by the symmetry conjugation of the density matrix. This method is conveni-ent. By this method, these formulas of different kinds for the pure system were deducedfirstly. Secondly, for the different quantum-number of spin, these quantum coherences ofdifferent kinds in four mixed systems were calculated. The numeral ratio and their sum ofquantum coherences were got. The formulas for the mixed system were deduced. Additionto the theoretical calculation, the meaning of the result of this study were briefly discussedalso.