State vector approximations for the resonant two-photon Jaynes-Cummings model

摘要

We report improved approximate state vectors for the resonant two-photon Jaynes-Cummings model. The results show that conventional practice of approximating the state vector via a Taylor series expansion up to the second-order term can be dramatically improved by the addition of a thirdorder term. Our new approximation is no more difficult to use than the conventional one.