二能级开放量子系统相干保持的最优控制策略

Optimal Control Strategy for Coherence-preserving Based on Two-level Open Quantum Systems

二能级量子系统在开放环境下的相干保持是量子器件实用化的关键。针对二能级开放量子系统的相干保持问题,首先将系统的主方程模型转化为实向量空间上的状态空间模型。然后借助经典最优控制的思想,提出了一种既保证系统控制能量最小,同时又最大程度的减小消相干的最优控制策略。最后就一个典型的二能级开放量子系统仿真实现其相干保持,仿真结果显示了该方案的优越性。

The coherence-preserving of two-level open quantum systems is recognized as a key to preserve the striking feature of the parallel character of the quantum information processing,which is crucial for implementing the quantum theory into reality. Aiming at the problem,in order to reduce this unexpected decoherence effect,the quantum master equation was mainly investigated. The orthogonal basis of geometric algebra was used to convert the quantum master equation into the state-space model, in which the useful coherent vector was attained. Then the corresponding recursive optimal control algorithm was designed to achieve both the maximal suppression of decoherence and the control energy minimizing based on a typical two-level quantum system. Afterwards,some tips of how to choose the parameters were discussed. Simulation results verify its effectiveness and superiority to coherence-preserving.