运用简并微扰的方法得到拉比模型在二阶微扰下的能量和一阶微扰下的波函数。所得结果在当前的实验参数范围内与数值模拟符合非常好。这一方法对求解拉比模型的系统能级具有指导意义,有益于拉比模型的进一步应用。

In this paper, the Rabi model is investigated on the degenerate perturbation theory. In the second-order approximation the energy is obtained and the wavefunctions is given in terms of the first-order approximation. The derived energy spectrums agree well with the direct numerical simulation in a certain range of the experimental parameters. This method has a guiding sense to solve the energy levels of the Rabi model, and is beneficial for further considering the application of the Rabi model.