Dirac cone intensity asymmetry and surface magnetic field in V-doped and pristine topological insulators generated by synchrotron and laser radiation

A M Shikin; A A Rybkina; D A Estyunin; D M Sostina; I I Klimovskikh; V Yu Voroshnin; A G Rybkin; K A Kokh; O E Tereshchenko; L Petaccia; G Di Santo; A Kimura; P N Skirdkov; K A Zvezdin; A K Zvezdin

doi:10.1038/s41598-018-24716-1

Dirac cone intensity asymmetry and surface magnetic field in V-doped and pristine topological insulators generated by synchrotron and laser radiation

Sci Rep. 2018 Apr 25;8(1):6544. doi: 10.1038/s41598-018-24716-1.

Authors

A M Shikin¹, A A Rybkina², D A Estyunin², D M Sostina², I I Klimovskikh², V Yu Voroshnin², A G Rybkin², K A Kokh^{2

3

4}, O E Tereshchenko^{2

3

5}, L Petaccia⁶, G Di Santo⁶, A Kimura⁷, P N Skirdkov^{8

9

10}, K A Zvezdin^{8

9

10}, A K Zvezdin^{8

9

10}

Affiliations

¹ Saint Petersburg State University, Saint Petersburg, 198504, Russia. [email protected].
² Saint Petersburg State University, Saint Petersburg, 198504, Russia.
³ Novosibirsk State University, Novosibirsk, 630090, Russia.
⁴ V.S. Sobolev Institute of Geology and Mineralogy, Novosibirsk, 630090, Russia.
⁵ A.V. Rzhanov Institute of Semiconductor Physics, Novosibirsk, 630090, Russia.
⁶ Elettra Sincrotrone Trieste, Trieste, 34149, Italy.
⁷ Graduate School of Science, Hiroshima University, Higashi-Hiroshima, 739-8526, Japan.
⁸ Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia.
⁹ A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, 119991, Russia.
¹⁰ Russian Quantum Center, Skolkovo, 143025, Russia.

Abstract

Effect of magnetization generated by synchrotron or laser radiation in magnetically-doped and pristine topological insulators (TIs) is presented and analyzed using angle-resolved photoemission spectroscopy. It was found that non-equal photoexcitation of the Dirac cone (DC) states with opposite momenta and spin orientation indicated by the asymmetry in photoemission intensity of the DC states is accompanied by the k_||-shift of the DC states relative to the non-spin-polarized conduction band states located at k_|| = 0. We relate the observed k_||-shift to the induced surface in-plane magnetic field and corresponding magnetization due to the spin accumulation. The direction of the DC k_||-shift and its value are changed with photon energy in correlation with variation of the sign and magnitude of the DC states intensity asymmetry. The theoretical estimations describe well the effect and predict the DC k_||-shift values which corroborate the experimental observations. This finding opens new perspectives for effective local magnetization manipulation.