Sergey Slizovskiy: Surface states of Bernal and rhombohedral graphite

posted 27 May 2019, 07:24 by info admin   [ updated 27 May 2019, 07:25 ]
National Graphene Institute, University of Manchester, M13 9PL, UK.

Graphite is semimetal allowing for unprecedented electrostatic control of its surface states via hBN encapsulation and gating. Graphite with Bernal (ABA) and rhombohedral (ABC) stacking have notably different electronic properties: Bernal graphite is a semimetal with small electron and hole Fermi surfaces and no surface states; Rhombohedral graphite is also a semimetal, but thin films thereof are insulating in the bulk and host 2D metallic surface states. We show that two types of surface states do appear at the surface of Bernal graphite upon electrostatic doping: (1) compressible surface states that form a 2D metal on the surface (red branch on the image) and (2) incompressible surface states that may appear above or below the Fermi level. The results are confirmed experimentally by quantum capacitance spectroscopy. For surface states in rhombohedral graphite films we calculate the phase diagram, predicting a pattern of gate-induced topological Lifshitz transitions between metallic surface states with different Fermi surface topology, we find a giant Berry curvature induced Hall coefficient and strong sensitivity of surface states to in-plane magnetic field. The theoretical results are confirmed by recent experiments carried in Manchester.

[1] J. Yin, S. Slizovskiy, Y. Cao, Sh. Hu, Y. Yang, I. Lobanova, B. Piot, S. Son,
S.Ozdemir, T. Taniguchi, K.Watanabe , K. Novoselov, F. Guinea, A. Geim , V.
Fal’ko , and A. Mishchenko, Nature Physics (2019), doi:10.1038/s41567-019-
0427-6 and a work in preparation

[2] S.Slizovskiy, E. McCann, M.Koshino, V.Fal’ko, in preparation

Sergey Slizovskiy is currently a postdoctoral member of theory group of Prof.
V.Fal'ko at National Graphene Institute, The University of Manchester, UK. He is interested in electronic properties of 2D materials, Quantum Hall Effect devices, topological insulators, edge states, Dirac and Weyl semimetals, topological Lifshitz transitions in interacting systems. He received his M.S. and PhD degrees in theoretical physics from Saint-Petersburg State University and a PhD in physics from Uppsala University, then spent 5 years at Loughborough University studying interacting electronic systems with strong spin fluctuations and graphene in magnetic field. His awards include EPSRC post-doctoral fellowship, PhD stipend of Russian noncommercial foundation Dynasty and RFBR (Russia) grants.