Creation of a squeezed photon distribution using artificial atoms with broken inversion symmetry

We consider a two-level system with both a transversal and a longitudinal coupling to the electromagnetic field of a resonator. Using a polaron transformation, this Hamiltonian can be mapped onto a Jaynes-Cummings Hamiltonian with generalized field operators acting on the electromagnetic field in the resonator. In contrast to the usual ladder operators a and a(dagger), these operators exhibit a nonmonotonous coupling strength with respect to the number n of photons in the resonator. In particular, there are roots of the coupling between qubit and resonator at certain photon numbers n(0). We show that this effect can be exploited to generate photon-number squeezed light, characterized by a Fano factor F << 1, with a large number of photons (e.g., of the order of 1 x 10(4)).