Document Type

Article

Publication Date

3-8-2013

Journal or Book Title

Physical Review B

Volume

87

Issue

12

First Page

125303

DOI

10.1103/PhysRevB.87.125303

Abstract

Formation energies of native defects in Bi2(TexSe3−x), with comparison to ideal Bi2Te2S, are calculated in density-functional theory to assess transport properties. Bi2Se3 is found to be n type for both Bi- and Se-rich growth conditions, while Bi2Te3 changes fromn to p type going from Te- to Bi-rich conditions, as observed. Bi2Te2Se and Bi2Te2S are generally n type, explaining observed heavily doped n-type behavior in most samples. A (0/−) transition level at 16 meV above valence-band maximum for Bi on Te antisites in Bi2Te2Se is related to the observed thermally active transport gap causing a p-to-n transition at low temperature. Bi2(TexSe3−x) with x>2 are predicted to have high bulk resistivity due to effective carrier compensation when approaching the n-to-pcrossover. Predicted behaviors are confirmed from characterization of our grown single crystals.

Comments

This article is from Physical Review B 87 (2013): 125303, doi:10.1103/PhysRevB.87.125303.

Copyright Owner

American Physical Society

Language

en

File Format

application/pdf

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