Control Decoherence by Quantum Generalized Measurement

This paper explores the potential of combating the decoherence by associating quantum generalized measurement with decoherence-free subspaces (DFS). It is demonstrated that associating quantum generalized subspace projector measurement (QGSPM) and quantum generalized case-projector measurement (QGCPM) with the operator conditions for DFS will enhance the capability of suppressing the decoherence for both Markovian and non-Markovian open quantum systems. It is emphasized that quantum measurement can be regarded as a means to manipulate quantum states. This method is advantageous because the coherent control Hamilton can be constructively designed.