Entropic evidence for a Pomeranchuk effect in magic-angle graphene

Nature
  • 1.

    Pomeranchuk, I. On the theory of He3. Zh. Eksp. Teor. Fiz 20, 919 (1950).

    CAS 

    Google Scholar
     

  • 2.

    Bistritzer, R. & MacDonald, A. H. Moiré bands in twisted double-layer graphene. Proc. Natl Acad. Sci. USA 108, 12233–12237 (2011).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 3.

    Cao, Y. et al. Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature 556, 80–84 (2018).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 4.

    Cao, Y. et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature 556, 43–50 (2018).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 5.

    Li, G. et al. Observation of Van Hove singularities in twisted graphene layers. Nat. Phys. 6, 109–113 (2010).

    Article 

    Google Scholar
     

  • 6.

    Suárez Morell, E., Correa, J. D., Vargas, P., Pacheco, M. & Barticevic, Z. Flat bands in slightly twisted bilayer graphene: tight-binding calculations. Phys. Rev. B 82, 121407 (2010).

    ADS 
    Article 

    Google Scholar
     

  • 7.

    Regan, E. C. et al. Mott and generalized Wigner crystal states in WSe2/WS2 moiré superlattices. Nature 579, 359–363 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 8.

    Tang, Y. et al. Simulation of Hubbard model physics in WSe2/WS2 moiré superlattices. Nature 579, 353–358 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 9.

    Yankowitz, M. et al. Tuning superconductivity in twisted bilayer graphene. Science 363, 1059–1064 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 10.

    Lu, X. et al. Superconductors, orbital magnets and correlated states in magic-angle bilayer graphene. Nature 574, 653–657 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 11.

    Nuckolls, K. P. et al. Strongly correlated Chern insulators in magic-angle twisted bilayer graphene. Nature 588, 610–615 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 12.

    Wu, S., Zhang, Z., Watanabe, K., Taniguchi, T. & Andrei, E. Y. Chern insulators and topological flat-bands in magic-angle twisted bilayer graphene. Preprint at https://arXiv.org/abs/2007.03735 (2020).

  • 13.

    Das, I. et al. Symmetry broken Chern insulators and magic series of Rashba-like Landau level crossings in magic angle bilayer graphene. Preprint at https://arXiv.org/abs/2007.13390 (2020).

  • 14.

    Sharpe, A. L. et al. Emergent ferromagnetism near three-quarters filling in twisted bilayer graphene. Science 365, 605–608 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 15.

    Serlin, M. et al. Intrinsic quantized anomalous Hall effect in a moiré heterostructure. Science 367, 900–903 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 16.

    Kerelsky, A. et al. Maximized electron interactions at the magic angle in twisted bilayer graphene. Nature 572, 95–100 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 17.

    Xie, Y. et al. Spectroscopic signatures of many-body correlations in magic-angle twisted bilayer graphene. Nature 572, 101–105 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 18.

    Jiang, Y. et al. Charge order and broken rotational symmetry in magic-angle twisted bilayer graphene. Nature 573, 91–95 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 19.

    Choi, Y. et al. Electronic correlations in twisted bilayer graphene near the magic angle. Nat. Phys. 15, 1174–1180 (2019); correction 15, 1205 (2019).

    CAS 
    Article 

    Google Scholar
     

  • 20.

    Tomarken, S. L. et al. Electronic compressibility of magic-angle graphene superlattices. Phys. Rev. Lett. 123, 046601 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 21.

    Zondiner, U. et al. Cascade of phase transitions and Dirac revivals in magic-angle graphene. Nature 582, 203–208 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 22.

    Po, H. C., Zou, L., Vishwanath, A. & Senthil, T. Origin of Mott insulating behavior and superconductivity in twisted bilayer graphene. Phys. Rev. X 8, 031089 (2018).

    CAS 

    Google Scholar
     

  • 23.

    Song, Z. et al. All magic angles in twisted bilayer graphene are topological. Phys. Rev. Lett. 123, 036401 (2019).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 24.

    Ahn, J., Park, S. & Yang, B.-J. Failure of Nielsen-Ninomiya theorem and fragile topology in two-dimensional systems with space-time inversion symmetry: application to twisted bilayer graphene at magic angle. Phys. Rev. X 9, 021013 (2019).

    CAS 

    Google Scholar
     

  • 25.

    Bultinck, N. et al. Ground state and hidden symmetry of magic-angle graphene at even integer filling. Phys. Rev. X 10, 031034 (2020).

    CAS 

    Google Scholar
     

  • 26.

    Kumar, A., Xie, M. & MacDonald, A. H. Lattice collective modes from a continuum model of magic-angle twisted bilayer graphene. Preprint at https://arXiv.org/abs/2010.05946 (2020).

  • 27.

    Wu, F. & Das Sarma, S. Collective excitations of quantum anomalous Hall ferromagnets in twisted bilayer graphene. Phys. Rev. Lett. 124, 046403 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 28.

    Wong, D. et al. Cascade of electronic transitions in magic-angle twisted bilayer graphene. Nature 582, 198–202 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 29.

    McWhan, D. B. et al. Electronic specific heat of metallic Ti-doped V2O3. Phys. Rev. Lett. 27, 941–943 (1971).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 30.

    Spivak, B. & Kivelson, S. A. Phases intermediate between a two-dimensional electron liquid and Wigner crystal. Phys. Rev. B 70, 155114 (2004).

    ADS 
    Article 

    Google Scholar
     

  • 31.

    Continentino, M. A., Ferreira, A. S., Pagliuso, P. G., Rettori, C. & Sarrao, J. L. Solid state Pomeranchuk effect. Physica B 359–361, 744–746 (2005).

    ADS 
    Article 

    Google Scholar
     

  • 32.

    Pustogow, A. et al. Quantum spin liquids unveil the genuine Mott state. Nat. Mater. 17, 773–777 (2018).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 33.

    Saito, Y. et al. Isospin Pomeranchuk effect in twisted bilayer graphene. Nature https://www.nature.com/articles/s41586-021-03409-2 (2021).

  • 34.

    Kuntsevich, A. Y., Tupikov, Y. V., Pudalov, V. M. & Burmistrov, I. S. Strongly correlated two-dimensional plasma explored from entropy measurements. Nat. Commun. 6, 7298 (2015).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 35.

    Hartman, N. et al. Direct entropy measurement in a mesoscopic quantum system. Nat. Phys. 14, 1083–1086 (2018).

    CAS 
    Article 

    Google Scholar
     

  • 36.

    Park, J. M., Cao, Y., Watanabe, K., Taniguchi, T. & Jarillo-Herrero, P. Flavour Hund’s coupling, correlated Chern gaps, and diffusivity in moiré flat bands. Preprint at https://arXiv.org/abs/2008.12296 (2020).

  • 37.

    Chen, S. et al. Electrically tunable correlated and topological states in twisted monolayer-bilayer graphene. Nature Phys. 17, 374–380 (2021).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 38.

    Spivak, B. & Kivelson, S. A. Transport in two dimensional electronic micro-emulsions. Ann. Phys. 321, 2071–2115 (2006).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 39.

    Cao, Y. et al. Strange metal in magic-angle graphene with near Planckian dissipation. Phys. Rev. Lett. 124, 076801 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

  • 40.

    Polshyn, H. et al. Large linear-in-temperature resistivity in twisted bilayer graphene. Nat. Phys. 15, 1011–1016 (2019).

    CAS 
    Article 

    Google Scholar
     

  • 41.

    Uri, A. et al. Mapping the twist-angle disorder and Landau levels in magic-angle graphene. Nature 581, 47–52 (2020).

    ADS 
    CAS 
    Article 

    Google Scholar
     

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