King's College London

Research portal

Entropy in the Non-Fermi-Liquid Regime of the Doped 2D Hubbard Model

Research output: Contribution to journalLetterpeer-review

Original languageEnglish
Article number105701
Pages (from-to)105701
JournalPhysical Review Letters
Issue number10
Published12 Mar 2021

Bibliographical note

Funding Information: This work was supported by Engineering and Physical Sciences Research Council (EPSRC) through Grant No. EP/P003052/1 and by the Simons Foundation as a part of the Simons Collaboration on the Many Electron Problem. We are grateful to the United Kingdom Materials and Molecular Modelling Hub for computational resources, which is partially funded by EPSRC (EP/P020194/1 and EP/T022213/1). Publisher Copyright: © 2021 American Physical Society. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.


King's Authors


We study thermodynamic properties of the doped Hubbard model on the square lattice in the regime of strong charge and spin fluctuations at low temperatures near the metal-to-insulator crossover and obtain results with controlled accuracy using the diagrammatic Monte Carlo method directly in the thermodynamic limit. The behavior of the entropy reveals a non-Fermi-liquid state at sufficiently high interactions near half filling: A maximum in the entropy at nonzero doping develops as the coupling strength is increased, along with an inflection point, evidencing a metal to non-Fermi-liquid crossover. The specific heat exhibits additional distinctive features of a non-Fermi-liquid state. Measurements of the entropy can, therefore, be used as a probe of the state of the system in quantum simulation experiments with ultracold atoms in optical lattices.

View graph of relations

© 2020 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454