Cho, Seong Won Kim, Kwang-Chon Kim, Seong Keun Cheong, Byung-Ki Kim, Jin-Sang Lee, Suyoun 2024-01-20T00:03:36Z 2024-01-20T00:03:36Z 2021-09-03 2017-11-05 0925-8388 https://pubs.kist.re.kr/handle/201004/122078 A topological insulator (TI), a new quantum state featured with the topologically-protected surface state (TSS) originating from its unique topology in band structure, has attracted much interest due to academic and practical importance. Nonetheless, a large contribution of the bulk conduction, induced by unintended doping by defects, has hindered the characterization of the surface state and the application of it into a device. To resolve this problem, we have investigated the transport properties of epitaxial Bi2-delta Sn delta Te3 thin films with varying delta. With the bulk conduction being strongly suppressed, the TSS is separately characterized, resulting in a large phase relaxation length of similar to 250 nm at 1.8 K. In addition, the magnetoresistance ratio (MR) has shown a non-monotonic temperature dependence with a maximum value at an elevated temperature depending on delta. These results are associated with the compensation of carriers and, we believe, provide an important step for the application of topological insulators for developing novel functional devices based on the topological surface states. (C) 2017 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE SA QUANTUM OSCILLATIONS SURFACE-STATES BI2TE3 FILMS MAGNETORESISTANCE Suppression of bulk conductivity and large phase relaxation length in topological insulator Bi2-delta Sn delta Te3 epitaxial thin films grown by Metal-Organic Chemical Vapor Deposition (MOCVD) Article 10.1016/j.jallcom.2017.06.342 1 JOURNAL OF ALLOYS AND COMPOUNDS, v.723, pp.942 - 947 JOURNAL OF ALLOYS AND COMPOUNDS 723 942 947 scie scopus 000407009400118 2-s2.0-85021632959 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article QUANTUM OSCILLATIONS SURFACE-STATES BI2TE3 FILMS MAGNETORESISTANCE Topological insulator Compensation doping Large phase-relaxation length