We study the ground state energy and ground states of systems coupling nonrelativistic
quantum particles and force-carrying Bose fields, such as radiation, in the quasiclassical …

We consider an electron coupled to the quantized radiation field in the dipole approximation.
Even if the Hamiltonian has no ground state at zero coupling, α=0, the interaction with the …

We establish general theorems on locating the essential spectrum of a self-adjoint operator
of the form A⊗ I+ I⊗ dΓ (S)+ HI on the tensor product H⊗ F b (K) of a Hilbert space H and the …

We prove existence of a ground state and resonances in the standard model of the non-
relativistic quantum electro-dynamics (QED). To this end we introduce a new canonical …

Ground states of Hamiltonian H of quantum field models are investigated. The infimum of the
spectrum of H is in the edge of its essential spectrum. By means of the asymptotic field …

The system of a one charged nonrelativistic particle with external potentials minimally
coupled to a massless quantized radiation field is considered. An ultraviolet cutoff is …

The purpose of this paper is to review recent advances in analysis of ground states of a
model in nonrelativistic quantum electrodynamics. It may be usually the fate of a physical or …

In this paper, we consider the spectrum of a model in quantum electrodynamics with a
spatial cutoff. It is proven that (1) the Hamiltonian is self-adjoint;(2) under the infrared …

We consider moving atoms and ions in R3 interacting with the quantized electromagnetic
field. Because of the translation invariance we consider the reduced Hamiltonian associated …

In this paper we study the semiclassical limit $\hslash\to 0$ of a completely solvable model
in quantum field theory: the van Hove model, describing a scalar field created and …