Finite temperature physics of $1D$ topological Kondo insulator: Stable Haldane phase, Emergent energy scale and Beyond

TL;DR

This study uses quantum Monte Carlo simulations to explore the finite-temperature behavior of a 1D topological Kondo insulator, revealing the stability of the Haldane phase, emergent energy scales, and boundary effects relevant for experiments.

Contribution

It provides the first detailed finite-temperature analysis of the 1D topological Kondo insulator, identifying an emergent energy scale and boundary phenomena beyond previous ground-state studies.

Findings

Haldane phase remains stable at finite temperature with edge magnetization.

Detection of free edge spins via spin structure factor and susceptibility.

Identification of a crossover temperature T_{cr} related to RKKY coupling.

Abstract

We have studied the one-dimensional $p$-wave periodic Anderson model at finite temperature with the help of the numerically exact determinant quantum Monte Carlo simulation. It is found that the topological Haldane phase established for ground-state is still stable against small thermal fluctuation and its characteristic edge magnetization develops at low temperature. Moreover, the saturated low-$T$ spin structure factor and the $\frac{1}{T}$-law of susceptibility are useful to detect the free edge spin moment, which may be relevant for experimental explorations. We have also comparatively studied the conventional $s$-wave periodic Anderson model, which helps us identify an emergent energy scale $T_{cr}$. $T_{cr}$ signals a crossover into interesting low-$T$ regime and seems to be the expected Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling. Finally, the collective Kondo screening effect has been examined and it is heavily reduced at boundary, which may give a fruitful playground for novel physics beyond the well-established Haldane state and topological band insulators.