Structural, Optical and Electronic Properties of the Wide Bandgap Topological Insulator Bi1.1Sb0.9Te2S | Sciact - CRIS-system of Boreskov Institute of Catalysis

Structural, Optical and Electronic Properties of the Wide Bandgap Topological Insulator Bi1.1Sb0.9Te2S Full article

Journal

Journal of Alloys and Compounds
ISSN: 0925-8388 , E-ISSN: 1873-4669

Output data

Year: 2022, Volume: 890, Article number : 161824, Pages count : 6 DOI: 10.1016/j.jallcom.2021.161824

Tags

Topological insulator; Bi1.1Sb0.9Te2S; Electronic structure; ARPES; Far infrared; Optical reflectivity

Authors

Khatchenko Yu E. ¹ , Yakushev M.V. ^1,2,3 , Seibel C. ⁴ , Bentmann H. ⁴ , Orlita M. ⁵ , Golyashov V. ⁶ , Ponosov Y.S. ^1,3 , Stepina N.P. ⁶ , Mudriy A.V. ⁷ , Kokh K.A. ^8,9,10 , Tereshchenko O.E. ^6,10 , Reinert F. ⁴ , Martin R.W. ¹¹ , Kuznetsova T.V. ^1,3

Affiliations

1	M.N. Miheev Institute of Metal Physics of UB RAS, 18 S. Kovalevskaya Str., Ekaterinburg 620108, Russia
2	Institute of Solid State Chemistry of the UB RAS, Ekaterinburg 620990, Russia
3	Ural Federal University, 19 Mira Str., Ekaterinburg 620002, Russia
4	Experimentelle Physik VII and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
5	LNCMI, 25 Martyrs Ave., BP 166, 38042 Grenoble Cedex 9, France
6	Rzhanov Institute of Semiconductor Physics of SB RAS, 13 Ac. Lavrentieva Ave., Novosibirsk 630090, Russia
7	Scientific-Practical Material Research Centre of NASB, 19 P. Brovki Str., Minsk 220072, Belarus
8	V.S. Sobolev Institute of Geology and Mineralogy of SB RAS, 3 Koptyuga Ave., Novosibirsk 630090, Russia
9	Kemerovo State University, 6 Krasnaya Str., Kemerovo 650000, Russia
10	Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia
11	Department of Physics, SUPA, Strathclyde University, 107 Rottenrow, Glasgow G4 0NG, UK

Successful applications of a topological insulator (TI) in spintronics require its bandgap to be wider then in a typical TI and the energy position of the Dirac point in the dispersion relations to be away from the valence and conduction bands. In this study we grew Bi1.1Sb0.9Te2S crystals and examined their elemental composition, structural, optical and electronic properties as well as the electronic band structure. The high structural quality of the grown crystals was established by X-ray diffraction and Raman spectroscopy. Angular resolved photoelectron spectroscopy demonstrated a near parabolic character of the valence and conduction bands and a direct bandgap of 0.36 eV. The dispersion relations also revealed a Dirac cone, confirming the topological insulator nature of this material, with the position of the Dirac point being 100 meV above the valence band maximum. Far infrared reflectivity spectra revealed a plasma edge and two phonon dips. Fitting these spectra with theoretical functions based on the Drude-Lorentz model allows determination of the high frequency dielectric constant (41.3), plasma frequency (936 cm−1) and the frequencies of two infrared phonons (177.7 cm−1 and 77.4 cm−1).

Khatchenko Y.E. , Yakushev M.V. , Seibel C. , Bentmann H. , Orlita M. , Golyashov V. , Ponosov Y.S. , Stepina N.P. , Mudriy A.V. , Kokh K.A. , Tereshchenko O.E. , Reinert F. , Martin R.W. , Kuznetsova T.V.
Structural, Optical and Electronic Properties of the Wide Bandgap Topological Insulator Bi1.1Sb0.9Te2S
Journal of Alloys and Compounds. 2022. V.890. 161824 :1-6. DOI: 10.1016/j.jallcom.2021.161824 WOS Scopus РИНЦ AN OpenAlex

Submitted:	Jun 4, 2021
Accepted:	Aug 30, 2021
Published online:	Sep 2, 2021
Published print:	Jan 15, 2022

Web of science:	WOS:000706835200004
Scopus:	2-s2.0-85114427301
Elibrary:	47044312
Chemical Abstracts:	2021:2008065
OpenAlex:	W3196515025

DB	Citing
Scopus	7
Web of science	8
OpenAlex	7