Transport Properties of (Bi,Sb)2Te3 Topological Insulator Crystals with Lateral p-n Junction | Sciact - CRIS-system of Boreskov Institute of Catalysis

Transport Properties of (Bi,Sb)2Te3 Topological Insulator Crystals with Lateral p-n Junction Full article

Journal

Physical Review Materials
, E-ISSN: 2475-9953

Output data

Year: 2023, Volume: 7, Number: 12, Article number : 124204, Pages count : DOI: 10.1103/physrevmaterials.7.124204

Authors

Golyashov V.A. ^1,2,3 , Kokh K.A. ⁴ , Tereshchenko O.E. ^1,2,3

Affiliations

1	Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
2	Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Kol'tsovo 630559, Russia
3	Novosibirsk State University, Novosibirsk 630090, Russia
4	Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia

High-quality low-bulk-carrier-concentration 3D topological insulator crystals and films are required for the majority of their potential applications. Creating a p-n transition using composition grading is one of the ways to obtain compensated regions in the bulk of 3D topological insulator crystals. Eventual formation of a p-n junction in 3D topological insulator surface states is expected to enhance the surface-transport-related spin filtering and charge-to-spin conversion. Here we report a detailed study of the transport and surface electronic structure of composition-graded Bi2Te3 and Bi1.34Sb0.66Te3 single crystals with built-in lateral p-n transition. The defect compensation naturally achieved at the p-n interface results in a strong reduction of the bulk carrier concentrations in both crystals. In the Bi2Te3 crystal a high-mobility n-type conductivity region is formed with electron Hall mobility of 70 000 cm2 V−1s−1 and Hall concentration of 2×1018cm−3 at 4.2 K. In the Bi1.34Sb0.66Te3 crystal the region of intrinsic conductivity with the lowest observed hole Hall concentration of 6×1017cm−3 and hole Hall mobility of 10 000 cm2V−1s−1 is formed in the vicinity of the p-n junction. The downward band bending was observed on the surface of the p-type conductivity region of the Bi2Te3 and Bi1.34Sb0.66Te3, providing an almost barrierless topological surface state electron channel with no topological p-n junction formed. The composition grading can be used as a reliable method of obtaining high-quality single crystals with relatively large areas of low bulk carrier concentrations and enhanced charge carrier mobility, which can be used in further nanoscale topological insulator device fabrication.

Golyashov V.A. , Kokh K.A. , Tereshchenko O.E.
Transport Properties of (Bi,Sb)2Te3 Topological Insulator Crystals with Lateral p-n Junction
Physical Review Materials. 2023. V.7. N12. 124204 . DOI: 10.1103/physrevmaterials.7.124204 WOS Scopus ANCAN OpenAlex publication_identifier_short.sciact_skif_identifier_type

Submitted:	Jul 20, 2023
Accepted:	Dec 4, 2023
Published print:	Dec 22, 2023
Published online:	Dec 22, 2023

Web of science:	WOS:001141776700005
Scopus:	2-s2.0-85180552207
Chemical Abstracts:	2024:159178
Chemical Abstracts (print):	185:358010
OpenAlex:	W4390104051
publication_identifier.sciact_skif_identifier_type:	1553

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OpenAlex	1
Scopus	1
Web of science	2