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arXiv · 1205.0197

Coexistence of two- and three-dimensional Shubnikov-de Haas oscillations in Ar^+ -irradiated KTaO_3

S. Harashima·C. Bell·M. Kim·T. Yajima·Y. Hikita·H. Y. Hwang
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Abstract

We report the electron doping in the surface vicinity of KTaO_3 by inducing oxygen-vacancies via Ar^+ -irradiation. The doped electrons have high mobility (> 10^4 cm^2/Vs) at low temperatures, and exhibit Shubnikov-de Haas oscillations with both two- and three-dimensional components. A disparity of the extracted in-plane effective mass, compared to the bulk values, suggests mixing of the orbital characters. Our observations demonstrate that Ar^+ -irradiation serves as a flexible tool to study low dimensional quantum transport in 5d semiconducting oxides.

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S. Harashima, C. Bell, M. Kim, T. Yajima, Y. Hikita, H. Y. Hwang. 2012-05-01. Coexistence of two- and three-dimensional Shubnikov-de Haas oscillations in Ar^+ -irradiated KTaO_3. https://doi.org/10.1103/physrevb.88.085102

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