Disorder-driven topological phase transition in Bi 2 Se 3 films

Matthew Brahlek, Nikesh Koirala, Maryam Salehi, Jisoo Moon, Wenhan Zhang, Haoxiang Li, Xiaoqing Zhou, Myung Geun Han, Liang Wu, Thomas Emge, Hang Dong Lee, Can Xu, Seuk Joo Rhee, Torgny Gustafsson, N. Peter Armitage, Yimei Zhu, Daniel S. Dessau, Weida Wu, Seongshik Oh

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

Topological insulators (TI) are a phase of matter that host unusual metallic surface states. Unlike the states that exist on the surface of conventional materials, these so-called topological surfaces states (TSS) are protected against disorder-related localization effects by time reversal symmetry through strong spin-orbit coupling. By combining transport measurements, angle-resolved photoemission spectroscopy, and scanning tunneling microscopy, we show that there exists a critical level of disorder beyond which the TI Bi2Se3 loses its ability to protect the metallic TSS and transitions to a fully insulating state. The absence of the metallic surface channels dictates that there is a change in the material's topological character, implying that disorder can lead to a topological phase transition even without breaking the time reversal symmetry. This observation challenges the conventional notion of topologically protected surface states and should prompt new studies as to the fundamental nature of topological phase of matter in the presence of disorder.

Original languageEnglish
Article number165104
JournalPhysical Review B
Volume94
Issue number16
DOIs
StatePublished - Oct 3 2016
Externally publishedYes

Funding

We thank Emil Prodan for helpful discussions. This work is supported by the National Science Foundation (Grants No. DMREF-1233349, No. DMR-1126468, No. DMR-1308142, No. DMR-1506618, No. DMR-1106070, and No. EFMA-1542798), Gordon and Betty Moore Foundation's EPiQS Initiative (GBMF4418) for S.O., US Department of Energy (DOE) (Contract No. DE-FG0203ER46066) for D.S.D., and Gordon and Betty Moore Foundation (GBMF2628) and Army Research Office (Grant No. W911NF-15-1-0560) for N.P.A. The work at Brookhaven National Lab is supported by the US DOE, Office of Basic Energy Science, Division of Materials Science and Engineering under Contract No. DESC0012704. The transmission electron microscopy sample preparation was carried out at the Center for Functional Nanomaterials, Brookhaven National Laboratory. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US DOE under Contract No. DE-AC02-05CH11231.

Fingerprint

Dive into the research topics of 'Disorder-driven topological phase transition in Bi 2 Se 3 films'. Together they form a unique fingerprint.

Cite this