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arXiv · 2105.02749

Visualization of optical polarization transfer to photoelectron spin vector emitted from the spin-orbit coupled surface state

Kenta Kuroda·Koichiro Yaji·Ryo Noguchi·Ayumi Harasawa·Shik Shin·Takeshi Kondo·Fumio Komori
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Abstract

Similar to light polarization that is selected by a superposition of optical basis, electron spin direction can be controlled through a superposition of spin basis. We investigate such a spin interference occurring in photoemission of the spin-orbit coupled surface state in Bi2Se3 by using spin- and angle-resolved photoemission spectroscopy combined with laser light source (laser-SARPES). Our laser-SARPES with three-dimensional spin detection and tunable laser polarization including elliptical and circular polarization enables us to directly visualize how the direction of the fully-polarized photoelectron spin changes according to the optical phase and orientation of the incident laser polarization. By this advantage of our laser-SARPES, we demonstrate that such optical information can be projected to the three-dimensional spin vector of the photoelectrons. Our results, therefore, present a novel spin-polarized electron source permitting us to optically control the pure spin state pointing to the arbitrary direction.

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Kenta Kuroda, Koichiro Yaji, Ryo Noguchi, Ayumi Harasawa, Shik Shin, Takeshi Kondo, Fumio Komori. 2021-05-06. Visualization of optical polarization transfer to photoelectron spin vector emitted from the spin-orbit coupled surface state. https://doi.org/10.1103/physrevb.105.l121106

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