基于隐李雅普诺夫量子控制的量子纯态调控

Regulation of Quantum Pure States Based on The Implicit Lyapunov Quamtum Control

已有研究结果表明,在封闭量子系统中,当被控系统满足强正则条件以及内部哈密顿量所有不同于目标态的本征态和目标态直接连接时,能够根据基于状态偏差的李雅普诺夫控制方法设计控制律使控制系统渐近稳定,但当被控系统不满足强正则或至少有一个本征态不和目标态连接时,被称为退化情况,情况将变的复杂.首先提出基于状态偏差的隐李雅普诺夫控制方法来解决这两种退化情况的收敛控制问题,将目标态从本征态拓展到了任意纯态.并且,所提出的方法也可以被用于控制退化情况下的多控制哈密顿量子系统.其次,研究了基于状态偏差和状态距离的隐李雅普诺夫控制方法的关系.最后,通过进行控制系统的数值仿真实验来验证提出的控制方法的正确性和有效性,并对基于状态偏差和状态距离的隐李雅普诺夫控制方法的控制效果进行对比.

In the closed quantum system, if the control system is strongly regular and all other eigenstates are directly coupled to the target state, the control system can be asymptotically stabilized at the target eigenstate by the Lyapunov control based on the state error. However, if the control system is not strongly regular or as long as there is one eigenstate not directly coupled to the target state, the situations will become complicated. In this paper, we propose an implicit Lyapunov control method based on the state error to solve the convergence problems for these two degenerate cases. And at the same time, we expand the target state from the eigenstate to the arbitrary pure state. Especially, the proposed method is also applicable in the control system with multi-control Hamiltonians. On this basis, the convergence of the control systems is analyzed using the LaSalle invariance principle. Furthermore, the relation between the implicit Lyapunov functions of the state distance and the state error is investigated. Finally, numerical simulations are carried out to verify the effectiveness of the proposed implicit Lyapunov control method. The comparisons of the control effect using the implicit Lyapunov control method based on the state distance with that of the state error are given.