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Glass Transition in a Two-Dimensional Electron System in Silicon in a Parallel Magnetic Field

J. Jaroszynski·Dragana Popovic·T. M. Klapwijk
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Abstract

Studies of low-frequency resistance noise show that the glassy freezing of the two-dimensional electron system (2DES) in Si in the vicinity of the metal-insulator transition (MIT) persists in parallel magnetic fields B of up to 9 T. At low B, both the glass transition density $n_g$ and $n_c$, the critical density for the MIT, increase with B such that the width of the metallic glass phase ($n_c<n_s<n_g$) increases with B. At higher B, where the 2DES is spin polarized, $n_c$ and $n_g$ no longer depend on B. Our results demonstrate that charge, as opposed to spin, degrees of freedom are responsible for glassy ordering of the 2DES near the MIT.

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J. Jaroszynski, Dragana Popovic, T. M. Klapwijk. 2003-02-25. Glass Transition in a Two-Dimensional Electron System in Silicon in a Parallel Magnetic Field. https://doi.org/10.1117/12.545304

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