主要探讨了非周期性量子行走中波函数的扩散性质。计算结果表明,通过在不同位置使用不同的幺正演化操作,能够精确调控多路径相干叠加态。不同的演化操作导致相干相长或者相干相消现象,从而对扩散性质产生影响。通过调节系统的演化参数,可改变行走者的扩散速率。量子行走扩散速率的研究有助于发展基于量子行走的新算法。

The diffusion property of wave functions in the non-periodic quantum walks is investigated in detail. The numerical results show that the multipath coherent superposition state can be precisely controlled by using position-dependent unitary evolution. Different evolutionary operations lead to the phenomenon of constructive or destructive interference and thus it affects the diffusion property. The diffusion speed of the walker can be changed by adjusting the evolution parameters of the system. The research on the diffusion speed of quantum walks is helpful to design new algorithms based on quantum walks.