Sampled-data design for decoherence control in open quantum system with operator errors

Application of quantum measurement to control system plays an important role in quantum information processing or other field. Since any real system must interact with surrounding environment, one has to consider the quantum measurement and control about open system. This paper investigates the problem of robustness for a single qubit with operator errors, which enlarges the field of quantum robustness control. It establishes control models on the basis of sliding mode control under Markovian noise, and defines control performance with indices as fidelity; coherence and purity that have real physical meanings. According to the different control targets, this paper presents the corresponding sliding mode design and the analytical expression of the data sampling period in a concrete Markovian environment. Furthermore, based on sampled-data control law, tracking the fidelity, coherence and purity of system and so on different state performance index, realizes the effective control of the operator error caused by the return of the coherent effect.