Positron surface state as a spectroscopic probe for characterizing surfaces of topological insulator materials

Vincent Callewaert, K. Shastry, Rolando Saniz, Ilja Makkonen, Bernardo Barbiellini, Badih A. Assaf, Donald Heiman, Jagadeesh S. Moodera, Bart Partoens, Arun Bansil, A. H. Weiss

Research output: Contribution to journalArticleScientificpeer-review

13 Citations (Scopus)
157 Downloads (Pure)

Abstract

Topological insulators are attracting considerable interest due to their potential for technological applications and as platforms for exploring wide-ranging fundamental science questions. In order to exploit, fine-tune, control, and manipulate the topological surface states, spectroscopic tools which can effectively probe their properties are of key importance. Here, we demonstrate that positrons provide a sensitive probe for topological states and that the associated annihilation spectrum provides a technique for characterizing these states. Firm experimental evidence for the existence of a positron surface state near Bi2Te2Se with a binding energy of Eb=2.7±0.2eV is presented and is confirmed by first-principles calculations. Additionally, the simulations predict a significant signal originating from annihilation with the topological surface states and show the feasibility to detect their spin texture through the use of spin-polarized positron beams.
Original languageEnglish
Article number115411
JournalPhysical Review B
Volume94
Issue number11
DOIs
Publication statusPublished - 6 Sep 2016
MoE publication typeA1 Journal article-refereed

Fingerprint Dive into the research topics of 'Positron surface state as a spectroscopic probe for characterizing surfaces of topological insulator materials'. Together they form a unique fingerprint.

Cite this