We investigate the specific heat, c, near an Ising nematic quantum critical point (QCP), using sign problem-free quantum Monte Carlo simulations. Cooling towards the QCP, we find a broad regime of temperature where c/T is close to the value expected from the non-interacting band structure, even for a moderately large coupling strength. At lower temperature, we observe a rapid rise of c/T, followed by a drop to zero as the system becomes superconducting. The spin susceptibility begins to drop at roughly the same temperature where the enhancement of c/T onsets, most likely due to the opening of a gap associated with superconducting fluctuations. These findings suggest that superconductivity and non-Fermi liquid behavior (manifested in an enhancement of the effective mass) onset at comparable energy scales. We support these conclusions with an analytical perturbative calculation.
@article{arxiv.2009.11280,
title = {Specific Heat of a Quantum Critical Metal},
author = {Ori Grossman and Johannes S. Hofmann and Tobias Holder and Erez Berg},
journal= {arXiv preprint arXiv:2009.11280},
year = {2021}
}