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Magnetoconductivity of Insulating Silicon Inversion Layers

Yeekin Tsui·S. A. Vitkalov·M. P. Sarachik·T. M. Klapwijk
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Abstract

The normalized in-plane magnetoconductivity of the dilute strongly interacting system of electrons in silicon MOSFET's scales with $B/T$ for low densities in the insulating phase. Pronounced deviations occur at higher metallic-like densities, where a new energy scale $k_B Δ$ emerges which is not associated with either magnetic field or thermal effects. $B/T$ scaling of the magnetoconductivity breaks down at the density $n_0$ where the energy scale $k_B Δ$ vanishes, near or at the critical density $n_c$ for the apparent metal-insulator transition. The different behavior of the magnetoconductivity at low and high densities suggests the existence of two distinct phases.

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Yeekin Tsui, S. A. Vitkalov, M. P. Sarachik, T. M. Klapwijk. 2003-12-09. Magnetoconductivity of Insulating Silicon Inversion Layers. https://arxiv.org/abs/cond-mat/0312218

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