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Effects of a Parallel Magnetic Field on the Metal-Insulator Transition in a Dilute Two-Dimensional Electron System

Kevin Eng·X. G. Feng·Dragana Popovic·S. Washburn
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Abstract

The temperature dependence of conductivity $σ(T)$ of a two-dimensional electron system in silicon has been studied in parallel magnetic fields B. At B=0, the system displays a metal-insulator transition at a critical electron density $n_c(0)$, and $dσ/dT >0$ in the metallic phase. At low fields ($B\lesssim 2$ T), $n_c$ increases as $n_c(B) - n_c(0) \propto B^β$ ($β\sim 1$), and the zero-temperature conductivity scales as $σ(n_s,B,T=0)/σ(n_s,0,0)=f(B^β/δ_n)$ (where $δ_n=(n_s-n_c(0))/n_c(0)$, and $n_s$ is electron density) as expected for a quantum phase transition. The metallic phase persists in fields of up to 18 T, consistent with the saturation of $n_c$ at high fields.

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Kevin Eng, X. G. Feng, Dragana Popovic, S. Washburn. 2002-04-23. Effects of a Parallel Magnetic Field on the Metal-Insulator Transition in a Dilute Two-Dimensional Electron System. https://doi.org/10.1103/physrevlett.88.136402

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