Effect of pressure on thermalization of one-dimensional nonlinear chains

TL;DR

This study investigates how pressure influences the thermalization process in one-dimensional nonlinear chains, revealing that pressure-induced nonintegrability changes affect thermalization times and transport properties.

Contribution

It demonstrates how pressure alters the nonintegrability and thermalization behavior of monatomic and disordered chains, offering new insights into pressure-dependent thermal transport.

Findings

Thermalization time is inversely proportional to the square of nonintegrability strength.

Pressure significantly changes the integrability of the system.

Different chains exhibit qualitatively different thermalization processes under pressure.

Abstract

Pressure plays a vital role in changing the transport properties of matter. To understand this phenomenon at a microscopic level, we here focus on a more fundamental problem, i.e., how pressure affects the thermalization properties of solids. As illustrating examples, we study the thermalization behavior of the monatomic chain and the mass-disordered chain of Fermi-Pasta-Ulam-Tsingou-$\beta$ under different strains in the thermodynamic limit. It is found that the pressure-induced change in nonintegrability results in qualitatively different thermalization processes for the two kinds of chains. However, for both cases, the thermalization time follows the same law -- it is inversely proportional to the square of the nonintegrability strength. This result suggests that pressure can significantly change the integrability of a system, which provides a new perspective for understanding the pressure-dependent thermal transport behavior.