Structural localization in the Classical and Quantum Fermi-Pasta-Ulam Model

TL;DR

This paper investigates how quantum effects influence the dynamics and statistical properties of the Fermi-Pasta-Ulam chain, revealing increased mobility at low temperatures due to zero-point energy and analyzing short-time quantum dispersion effects.

Contribution

It provides a comparative analysis of classical and quantum Fermi-Pasta-Ulam chains, highlighting quantum-induced mobility changes and short-time dynamical behavior.

Findings

Increased mobility at low temperatures in quantum chains

Quantum dispersion affects short-time configurational correlations

Zero-point energy significantly influences classical-quantum differences

Abstract

We study the statistics and short-times dynamics of the classical and the quantum Fermi-Pasta-Ulam chain in thermal equilibrium. We analyze the distributions of single-particle configurations by integrating out the rest of the system. At low temperatures we observe a systematic increase in the mobility of the chain when transitioning from classical to quantum mechanics due to zero-point energy effects. We analyze the consequences of the quantum dispersion on the dynamics at short times of configurational correlation functions.