Using two methods we show that a quantized discrete breather in a 1-D lattice is stable. One method uses path integrals and compares correlations for a (linear) local mode with those of the quantum breather. The other takes a local mode as the zeroth order system relative to which numerical, cutoff-insensitive diagonalization of the Hamiltonian is performed.
@article{arxiv.cond-mat/0601209,
title = {Stability of quantum breathers},
author = {L. S. Schulman and D. Tolkunov and E. Mihokova},
journal= {arXiv preprint arXiv:cond-mat/0601209},
year = {2009}
}