Magnetic-impurity-induced Modifications to Ultrafast Carrier Dynamics in the Ferromagnetic Topological Insulators Sb2−xVxTe3 | Sciact - CRIS-system of Boreskov Institute of Catalysis

Magnetic-impurity-induced Modifications to Ultrafast Carrier Dynamics in the Ferromagnetic Topological Insulators Sb2−xVxTe3 Full article

Journal

New Journal of Physics
ISSN: 1367-2630

Output data

Year: 2019, Volume: 21, Number: 9, Article number : 093006, Pages count : 9 DOI: 10.1088/1367-2630/ab3ac6

Tags

topological insulator, time- and angle-resolved photoemission spectroscopy, x-ray magnetic circular dichroism, scanning tunneling microscopy/spectroscopy

Authors

Sumida K. ^1,2 , Kakoki M. ¹ , Reimann J. ³ , Nurmamat M. ¹ , Goto S. ¹ , Takeda Y. ⁴ , Saitoh Y. ⁴ , Kokh K.A. ^5,6,7 , Tereshchenko O.E. ^6,7,8 , Güdde J. ³ , Höfer U. ³ , Kimura A. ¹

Affiliations

1	Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
2	Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551, Japan
3	Department of Physics and Materials Sciences Center, Philipps-University, D-35032 Marburg, Germany
4	Condensed Matter Science Division, Quantum Beam Science Center, Japan Atomic Energy Agency, Sayo, Hyogo 679-5148, Japan
5	Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences, Koptyuga pr. 3, 630090 Novosibirsk, Russia
6	Physics Department, Novosibirsk State University, ul. Pirogova 2, 630090 Novosibirsk, Russia
7	Physics Department, Saint Petersburg State University, Saint Petersburg, 198504, Russia
8	Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, pr. Akademika Lavrent’eva 13, 630090 Novosibirsk, Russia

Quantum anomalous Hall effect (QAHE) is a key phenomenon for low power-consumption device applications owing to its dissipationless spin-polarized and quantized current in the absence of an external magnetic field. However, the recorded working temperature of the QAHE is still very low. Here we systematically investigate the magnetic dopants induced modifications from the view points of magnetic, structural and electronic properties and the ultrafast carrier dynamics in a series of V-doped Sb2Te3 samples of composition Sb2−xVxTe3 with x = 0, 0.015 and 0.03. Element specific x-ray magnetic circular dichroism signifies that the ferromagnetism of V-doped Sb2Te3 is governed by the p–d hybridization between the host carrier and the magnetic dopant. Time- and angle-resolved photoemission spectroscopy excited with mid-infrared pulses has revealed that the V impurity induced states underlying the topological surface state (TSS) add scattering channels that significantly shorten the duration of transient surface electrons down to the 100 fs scale. This is in a sharp contrast to the prolonged duration reported for pristine samples though the TSS is located inside the bulk energy gap of the host in either magnetic or non-magnetic cases. It implies the presence of a mobility gap in the bulk energy gap region of the host material that would work toward the robust QAHE. Our findings shed light on the material design for low-energy-consuming device applications.

Sumida K. , Kakoki M. , Reimann J. , Nurmamat M. , Goto S. , Takeda Y. , Saitoh Y. , Kokh K.A. , Tereshchenko O.E. , Güdde J. , Höfer U. , Kimura A.
Magnetic-impurity-induced Modifications to Ultrafast Carrier Dynamics in the Ferromagnetic Topological Insulators Sb2−xVxTe3
New Journal of Physics. 2019. V.21. N9. 093006 :1-9. DOI: 10.1088/1367-2630/ab3ac6 WOS AN OpenAlex

Submitted:	Apr 22, 2019
Accepted:	Jul 7, 2019
Published print:	Sep 4, 2019

Web of science:	WOS:000484521700006
Chemical Abstracts:	2020:1921508
OpenAlex:	W2972004313

DB	Citing
OpenAlex	13
Web of science	11