Journal of Mathematical Physics

Perturbations of ground states in weakly interacting quantum spin systems

Dmitry Yarotsky

Published May 7, 2004• 13 citations

Abstract

We consider a general weak bounded finite range perturbation of a general free quantum spin Hamiltonian on a lattice. We prove that if the free Hamiltonian has a nondegenerate ground state and a spectral gap, then the perturbation also has a ground state, and estimate the localization of the spectrum in the corresponding ground state representation.

DOI: 10.1063/1.1705718

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