Gigantic 2D Laser-Induced Photovoltaic Effect in Magnetically Doped Topological Insulators for Surface Zero-Bias spin-Polarized Current Generation | Sciact - CRIS-system of Boreskov Institute of Catalysis

Gigantic 2D Laser-Induced Photovoltaic Effect in Magnetically Doped Topological Insulators for Surface Zero-Bias spin-Polarized Current Generation Full article

Journal

2D Materials
, E-ISSN: 2053-1583

Output data

Year: 2018, Volume: 5, Number: 1, Article number : 015015, Pages count : 9 DOI: 10.1088/2053-1583/aa928a

Tags

electronic and spin structure, 2D systems, time-resolved photoemission spectroscopy, spin-polarized currents, magnetically doped topological insulators, surface photovoltaic effect

Authors

Shikin A M ¹ , Voroshin V Yu ¹ , Rybkin A G ¹ , Kokh K A ^1,2,3 , Tereshchenko O E ^1,2,4 , Ishida Y ⁵ , Kimura A ⁶

Affiliations

1	Saint Petersburg State University, Saint Petersburg 198504, Russia
2	Novosibirsk State University, Novosibirsk 630090, Russia
3	V.S. Sobolev Institute of Geology and Mineralogy, Novosibirsk 630090, Russia
4	A.V. Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090, Russia
5	Institute for Solid State Physics, the University of Tokyo, Kashiwa, Chiba 277-8581, Japan
6	Graduate School of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526, Japan

A new kind of 2D photovoltaic effect (PVE) with the generation of anomalously large surface photovoltage up to 210 meV in magnetically doped topological insulators (TIs) has been studied by the laser time-resolved pump-probe angle-resolved photoelectron spectroscopy. The PVE has maximal efficiency for TIs with high occupation of the upper Dirac cone (DC) states and the Dirac point located inside the fundamental energy gap. For TIs with low occupation of the upper DC states and the Dirac point located inside the valence band the generated surface photovoltage is significantly reduced. We have shown that the observed giant PVE is related to the laser-generated electron–hole asymmetry followed by accumulation of the photoexcited electrons at the surface. It is accompanied by the 2D relaxation process with the generation of zero-bias spin-polarized currents flowing along the topological surface states (TSSs) outside the laser beam spot. As a result, the spinpolarized current generates an effective in-plane magnetic field that is experimentally confirmed by the kII-shift of the DC relative to the bottom non-spin-polarized conduction band states. The realized 2D PVE can be considered as a source for the generation of zero-bias surface spin-polarized currents and the laser-induced local surface magnetization developed in such kind 2D TSS materials.

Shikin A.M. , Voroshin V.Y. , Rybkin A.G. , Kokh K.A. , Tereshchenko O.E. , Ishida Y. , Kimura A.
Gigantic 2D Laser-Induced Photovoltaic Effect in Magnetically Doped Topological Insulators for Surface Zero-Bias spin-Polarized Current Generation
2D Materials. 2018. V.5. N1. 015015 :1-9. DOI: 10.1088/2053-1583/aa928a WOS Scopus ANCAN OpenAlex

Submitted:	Jun 29, 2017
Accepted:	Oct 11, 2017
Published online:	Oct 26, 2017
Published print:	Jan 1, 2018

Web of science:	WOS:000413836300001
Scopus:	2-s2.0-85040099677
Chemical Abstracts:	2018:2317534
Chemical Abstracts (print):	175:464261
OpenAlex:	W2762984597

DB	Citing
Scopus	3
OpenAlex	3
Web of science	4