Kinks: Fingerprints of strong electronic correlations

TL;DR

This paper reveals that strongly correlated electrons induce a kink in the low-temperature electronic specific heat, challenging the traditional linear temperature dependence assumption in solid state physics.

Contribution

It demonstrates that strong electronic correlations cause a kink in the specific heat, extending the conventional understanding of low-temperature thermodynamic behavior.

Findings

Kink appears in the specific heat due to strong correlations

Traditional linear temperature dependence is incomplete

Strong correlations modify low-temperature thermodynamics

Abstract

The textbook knowledge of solid state physics is that the electronic specific heat shows a linear temperature dependence with the leading corrections being a cubic term due to phonons and a cubic-logarithmic term due to the interaction of electrons with bosons. We have shown that this longstanding conception needs to be supplemented since the generic behavior of the low-temperature electronic specific heat includes a kink if the electrons are sufficiently strongly correlated