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arXiv · 1804.07012

Giant Rashba splitting of quasi-1D surface states on Bi/InAs(110)-(2$\times$1)

T. Nakamura·Y. Ohtsubo·Y. Yamashita·S. Ideta·K. Tanaka·K. Yaji·A. Harasawa·S. Shin·F. Komori·R. Yukawa·K. Horiba·H. Kumigashira·S. Kimura
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Abstract

Electronic states on the Bi/InAs(110)-(2$\times$1) surface and its spin-polarized structure are revealed by angle-resolved photoelectron spectroscopy (ARPES), spin-resolved ARPES, and density-functional-theory calculation. The surface state showed quasi-one-dimensional (Q1D) dispersion and a nearly metallic character; the top of the hole-like surface band is just below the Fermi level. The size of the Rashba parameter ($α_{\rm R}$) reached quite a large value ($\sim$5.5 eVÅ). The present result would provide a fertile playground for further studies of the exotic electronic phenomena in 1D or Q1D systems with the spin-split electronic states as well as for advanced spintronic devices.

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T. Nakamura, Y. Ohtsubo, Y. Yamashita, S. Ideta, K. Tanaka, K. Yaji, A. Harasawa, S. Shin, F. Komori, R. Yukawa, K. Horiba, H. Kumigashira, S. Kimura. 2018-08-04. Giant Rashba splitting of quasi-1D surface states on Bi/InAs(110)-(2$\times$1). https://doi.org/10.1103/physrevb.98.075431

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