The effect of finite mass in cavity QED calculations

Abstract: The effect of finite nuclear mass is investigated in coupled light matter systems in cavity quantum electrodynamics (cavity QED) using the Pauli-Fierz Hamiltonian. Three different systems, the He atom, the H$^-$ ion and the H$_2^+$ ion is investigated. There are small, but significant differences in the behavior of the binding energies as the function of the coupling strength. The probability of coupling to light is found to be very small but even this small coupling has a very strong effect on the energies of the systems.