【摘要】 针对哈密顿量具有波动的、大量成员系统构成的开放量子系综,在密度矩阵的相干矢量体系下提出了一个双阶段近似时间最优控制算法,实现了系综中所有成员系统对于一个共同目标态的高保真度状态转移,同时确保了控制时间的近似最小.该算法首先根据表征系综哈密顿量波动情况的参数分布律对系综进行采样以便得到代表系综特性的一个样本系统集;然后基于该样本系统集、并借助基本的梯度法在两个阶段中分别对保真度和控制时间进行优化,得到了最终的最优控制律;最后在两能级开放量子系综上进行了数值仿真实验,验证了所提出算法的有效性.更多还原

【Abstract】 For open quantum ensembles with Hamiltonian fluctuations composed of a large number of single quantum systems, a two-stage approximate time-optimal control algorithm is proposed in the framework of coherence vectors of density matrices and achieves a high-fidelity state transition of all member systems to a common target state within an approximate minimum control time. According to the parameter distribution rule that characterizes Hamiltonian fluctuations, this algorithm first samples the whole ensemble to obtain a sample system set. Then, based on the obtained sample system set and via the basic gradient method, the fidelity and the control time are optimized in the two stages respectively, and the resulting optimal control law is obtained. Numerical simulation experiments on a two-level open quantum ensemble verify the effectiveness of the proposed algorithm.更多还原