几类相干态的量子保真度

Fidelity of several kinds of coherence states

在坐标表象下,研究了几类相干态的量子保真度,对于相干态,我们给出了量子保真度的解析表达式,考查了谐振子特征长度L,平移距离x_0对保真度的影响;对于相干态|α〉与|-α〉的叠加态,考查了初态量子干涉对量子保真度的影响,结论表明:量子保真度呈周期性;与相干态的量子保真度比较而言,当谐振子处于第二类相干态时,量子干涉能抑制量子态失真,当谐振子处于第三类相干态时,量子干涉能抑制量子态失真,也可能加大量子态失真.

We investigate the fidelity of several kinds of coherence states in the coordinate representation, and the analytic expression was given for coherence state,the relation between the fidelity and the character length and translation distance was discussed,and the influences of quantum interference of the initial state on the fidelity are discussed for superposition state of |α〉and |-α〉.The results show that the fidelity evolved periodic;compared to fidelity of the coherence state,quantum interference can decrease the distortion of state when harmonic oscillator is in the second kind of coherence states,and quantum interference can decrease the distortion or increase the distortion when harmonic oscillator is in the third kind of coherence states.