Large tunable intrinsic gap in rhombohedral-stacked tetralayer graphene at half filling. (2nd August 2018)

• Record Type: Journal Article
• Authors: Myhro, K; Che, S; Shi, Y; Lee, Y; Thilahar, K; Bleich, K; Smirnov, D; Lau, C N
• Is Part Of: 2D materials. Volume 5:Number 4(2018)
• Publication Date: 2018-08-02
• Subjects: tetralayer graphene -- electronic interactions -- spontaneous symmetry breaking -- layer antiferromagnet -- half filling; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/aad2f2
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: At half filling, the very flat energy bands in rhombohedral-stacked tetralayer graphene are unstable to electronic interactions, giving rise to electronic states with spontaneous broken symmetries. Using transport measurements on suspended dual-gated devices, we observe an insulating ground state with a large interaction-induced transport gap up to 80 meV, which can be enhanced by a perpendicular magnetic field, and suppressed by an interlayer potential, carrier density, or a critical temperature of ~40 K. This insulating gapped state is proposed to be a layer antiferromagnet with broken time reversal symmetry.