Strong electronic interaction and multiple quantum Hall ferromagnetic phases in trilayer graphene

• Published in: Nature communications 2017-02, Vol.8 (1), p.14518-14518, Article 14518
• Main Authors: Datta, Biswajit, Dey, Santanu, Samanta, Abhisek, Agarwal, Hitesh, Borah, Abhinandan, Watanabe, Kenji, Taniguchi, Takashi, Sensarma, Rajdeep, Deshmukh, Mandar M.
• Format: Article
• Language: English
• Subjects: 639/766/119/2793; 639/766/119/2794; 639/766/119/2795; 639/925/918/1052; Electrons; Graphene; Humanities and Social Sciences; Materials science; multidisciplinary; Physics; Science; Science (multidisciplinary); Symmetry
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms14518

Quantum Hall effect provides a simple way to study the competition between single particle physics and electronic interaction. However, electronic interaction becomes important only in very clean graphene samples and so far the trilayer graphene experiments are understood within non-interacting electron picture. Here, we report evidence of strong electronic interactions and quantum Hall ferromagnetism seen in Bernal-stacked trilayer graphene. Due to high mobility ∼500,000 cm 2 V −1 s −1 in our device compared to previous studies, we find all symmetry broken states and that Landau-level gaps are enhanced by interactions; an aspect explained by our self-consistent Hartree–Fock calculations. Moreover, we observe hysteresis as a function of filling factor and spikes in the longitudinal resistance which, together, signal the formation of quantum Hall ferromagnetic states at low magnetic field. Few-layered graphene offers a powerful platform to investigate electronic interactions beyond the non-interacting electron picture approximation. Here, the authors report the signature of strong electronic interactions and quantum Hall ferromagnetism in trilayer graphene with ABA stacking.