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arXiv · 0706.3552

Strongly enhanced effective mass in dilute two-dimensional electron systems: System-independent origin

A. A. Shashkin·A. A. Kapustin·E. V. Deviatov·V. T. Dolgopolov·Z. D. Kvon
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Abstract

We measure the effective mass in a dilute two-dimensional electron system in (111)-silicon by analyzing temperature dependence of the Shubnikov-de Haas oscillations in the low-temperature limit. A strong enhancement of the effective mass with decreasing electron density is observed. The mass renormalization as a function of the interaction parameter r_s is in good agreement with that reported for (100)-silicon, which shows that the relative mass enhancement is system- and disorder-independent being determined by electron-electron interactions only.

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A. A. Shashkin, A. A. Kapustin, E. V. Deviatov, V. T. Dolgopolov, Z. D. Kvon. 2007-11-21. Strongly enhanced effective mass in dilute two-dimensional electron systems: System-independent origin. https://doi.org/10.1103/physrevb.76.241302

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