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arXiv · 0901.1873

Spin-Orbit Scattering and Quantum Metallicity in Ultra-Thin Be Films

Y. M. Xiong·A. B. Karki·D. P. Young·P. W. Adams
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Abstract

We compare and contrast the low temperature magnetotransport properties of ultra-thin, insulating, Be films with and without spin-orbit scattering (SOS). Beryllium films have very little intrinsic SOS, but by "dusting" them with sub-monolayer coverages of Au, one can introduce a well controlled SOS rate. Pure Be films with sheet resistance R >R_Q exhibit a low-temperature negative magnetoresistance (MR) that saturates to the quantum resistance R_Q = h/e^2. This high-field quantum metal phase is believed to represent a new ground state of the system. In contrast, the corresponding negative MR in Be/Au films is greatly diminished, suggesting that, in the presence of strong SOS, the quantum metal phase can only be reached at field scales well beyond those typically available in a low temperature laboratory.

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Y. M. Xiong, A. B. Karki, D. P. Young, P. W. Adams. 2009-01-13. Spin-Orbit Scattering and Quantum Metallicity in Ultra-Thin Be Films. https://arxiv.org/abs/0901.1873

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