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arXiv · 1005.5450

Direct evidence of spin-split one-dimensional metallic surface state on Si(557)-Au

Taichi Okuda·Koji Miyamoto·Yasuo Takeichi·Hirokazu Miyahara·Manami Ogawa·Ayumi Harasawa·Akio Kimura·Iwao Matsuda·Akito Kakizaki·Tatsuya Shishidou·Tamio Oguchi
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Abstract

We report unprecedented evidence of a spin split one-dimensional metallic surface state for the system of Si(557)-Au obtained by means of high-resolution spin- and angle-resolved photoelectron spectroscopy combined with first principles calculations. The surface state shows double parabolic energy dispersions along the Au chain structure together with a reversal of the spin polarization with respect to the time-reversal symmetry point as is characteristic from the Rashba effect. Moreover, we have observed a considerably large out-of-plane spin polarization which we attribute to the highly anisotropic wave function of the gold chains.

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Taichi Okuda, Koji Miyamoto, Yasuo Takeichi, Hirokazu Miyahara, Manami Ogawa, Ayumi Harasawa, Akio Kimura, Iwao Matsuda, Akito Kakizaki, Tatsuya Shishidou, Tamio Oguchi. 2010-05-29. Direct evidence of spin-split one-dimensional metallic surface state on Si(557)-Au. https://doi.org/10.1103/physrevb.82.161410

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