p-type Bi2Se3 for topological insulator and low-temperature thermoelectric applications

被引：575

作者：

Hor, Y. S. ^{[1
]}

Richardella, A. ^{[2
]}

Roushan, P. ^{[2
]}

Xia, Y. ^{[2
]}

Checkelsky, J. G. ^{[2
]}

Yazdani, A. ^{[2
]}

Hasan, M. Z. ^{[2
]}

Ong, N. P. ^{[2
]}

Cava, R. J. ^{[1
]}

机构：

[1] Princeton Univ, Dept Chem, Princeton, NJ 08544 USA

[2] Princeton Univ, Dept Phys, Princeton, NJ 08544 USA

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 19期

基金：

美国国家科学基金会;

关键词：

bismuth compounds; crystal defects; crystal growth; Fermi level; insulators; photoelectron spectra; scanning tunnelling microscopy; Seebeck effect; valence bands; N-TYPE BI2SE3; TRANSPORT; BISMUTH;

D O I：

10.1103/PhysRevB.79.195208

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The growth and elementary properties of p-type Bi2Se3 single crystals are reported. Based on a hypothesis about the defect chemistry of Bi2Se3, the p-type behavior has been induced through low-level substitutions (1% or less) of Ca for Bi. Scanning tunneling microscopy is employed to image the defects and establish their charge. Tunneling and angle-resolved photoemission spectra show that the Fermi level has been lowered into the valence band by about 400 meV in Bi1.98Ca0.02Se3 relative to the n-type material. p-type single crystals with ab-plane Seebeck coefficients of +180 mu V/K at room temperature are reported. These crystals show an anomalous peak in the Seebeck coefficient at low temperatures, reaching +120 mu V K-1 at 7 K, giving them a high thermoelectric power factor at low temperatures. In addition to its interesting thermoelectric properties, p-type Bi2Se3 is of substantial interest for studies of technologies and phenomena proposed for topological insulators.

引用

页数：5

共 26 条

[1] Electrical and thermoelectrical properties of Bi2Se3 grown by metal organic chemical vapour deposition technique [J].