POSSIBLE METAL-INSULATOR-TRANSITION AT B=0 IN 2 DIMENSIONS

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关键词: SILICON INVERSION-LAYERS;    2D ELECTRON-SYSTEM;    LOW-TEMPERATURES;    DEPENDENCE;    FILMS;    GAS;   

DOI  :  10.1103/PhysRevB.50.8039

来源: SCIE

【 摘 要 】

We have studied the zero magnetic field resistivity rho of unique high-mobility two-dimensional electron systems in silicon. At very low electron density n(s) (but higher than some sample-dependent critical value n(cr) similar to 10(11) cm(-2)), conventional weak localization is overpowered by a sharp drop of rho by an order of magnitude with decreasing temperature below similar to 1-2 K. No further evidence for electron localization is seen down to at least 20 mK. For n(s) < n(cr), the sample is insulating. The resistance is empirically found to scale with temperature both below and above n(cr) with a single parameter that approaches zero at n(s) = n(cr) suggesting a metal-insulator phase transition.

【 授权许可】

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