title: Generalized rotating-wave approximation for arbitrarily large coupling.
abstract: A generalized version of the rotating-wave approximation for the single-mode spin-boson Hamiltonian is presented. It is shown that performing a simple change of basis prior to eliminating the off-resonant terms results in a significantly more accurate expression for the energy levels of the system. The generalized approximation works for all values of the coupling strength and for a wide range of detuning values, and may find applications in solid-state experiments.
authors.affiliation: School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom. e.irish@qub.ac.uk
authors.forename: E K
authors.initials: EK
authors.lastname: Irish