Collective enhancement of low-order eigenmicrostates underlying heat-current reversal in periodically driven Frenkel-Kontorova lattices
Phys. Rev. E 114, 044134 – Published 19 October, 2026
DOI: https://doi.org/10.1103/k7yc-t6l6
Abstract
Frequency-dependent directed heat transport and heat-current reversal have been identified in nonlinear asymmetric lattices driven by a zero-mean thermal bias, but the microscopic dynamics associated with heat-current reversal remain incompletely understood. Here we introduce an eigenmicrostate-based approach to characterize the internal dynamical structure associated with heat-current reversal by constructing a kinetic-energy microstate matrix from steady-state trajectories and analyzing its dominant fluctuation patterns using singular-value decomposition and low-rank reconstruction. The results show that the kinetic-energy fluctuations near the reversal frequency are not dominated by a single isolated mode; rather, several low-order eigenmicrostates are enhanced concurrently, and the low-rank-reconstructed fluctuations exhibit stronger short-range spatial correlations near the reversal point. These results provide a microscopic structural picture of heat-current reversal in nonlinear lattices driven by a periodically modulated heat reservoir under zero-mean thermal bias and establish an eigenmicrostate-based framework for studying and controlling heat transport in low-dimensional systems.
