Communications in Theoretical Physics
A Class of Quasi-exact Solutions of Rabi Hamiltonian
Feng Pan, Yao You-Kun, Mingxia Xie, Han Wen-Juan, Jerry Paul Draayer
Abstract
A class of quasi-exact solutions of the Rabi Hamiltonian, which describes a two-level atom interacting with a single-mode radiation field via a dipole interaction without the rotating-wave approximation, are obtained by using a wavefunction ansatz. Exact solutions for part of the spectrum are obtained when the atom-field coupling strength and the field frequency satisfy certain relations. As an example, the lowest exact energy level and the corresponding atom-field entanglement at the quasi-exactly solvable point are calculated and compared to results from the Jaynes–Cummings and counter-rotating cases of the Rabi Hamiltonian.