The weak-coupled two-level open quantum system described by non-Markovian time-convolution-less master equation is investigated in this paper. The system characteristics with respect to the decay rate β(t), coherence factor Coh and purity p in terms of the cut-off frequency ωc, coupling constant α and transition frequency ωo are investigated, respectively. The appropriate parameters used in system simulation experiments are determined by analyzing results of different valu
