Structure and time-dependence of quantum breathers

TL;DR

This paper investigates the stability and properties of quantum breathers using numerical and path integral methods, revealing their stability apart from quantum tunneling effects.

Contribution

It introduces a combined numerical and path integral approach focusing on the central nonlinearity to analyze quantum breathers.

Findings

Quantum breathers are stable except for quantum tunneling.

The methods effectively reduce truncation effects in calculations.

Quantum localization persists in the studied models.

Abstract

Quantum states of a discrete breather are studied in two ways. One method involves numerical diagonalization of the Hamiltonian, the other uses the path integral to examine correlations in the eigenstates. In both cases only the central nonlinearity is retained. To reduce truncation effects in the numerical diagonalization, a basis is used that involves a quadratic local mode. A similar device is used in the path integral method for deducing localization. Both approaches lead to the conclusion that aside from quantum tunneling the quantized discrete breather is stable.