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Scaling and the Metal-Insulator Transition in Si/SiGe Quantum Wells

J. Lam·M. D'Iorio·D. Brown·H. Lafontaine
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Abstract

The existence of a metal-insulator transition at zero magnetic field in two- dimensional electron systems has recently been confirmed in high mobility Si-MOSFETs. In this work, the temperature dependence of the resistivity of gated Si/SiGe/Si quantum well structures has revealed a similar metal- insulator transition as a function of carrier density at zero magnetic field. We also report evidence for a Coulomb gap in the temperature dependence of the resistivity of the dilute 2D hole gas confined in a SiGe quantum well. In addition, the resistivity in the insulating phase scales with a single parameter, and is sample independent. These results are consistent with the occurrence of a metal-insulator transition at zero magnetic field in SiGe square quantum wells driven by strong hole-hole interactions.

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J. Lam, M. D'Iorio, D. Brown, H. Lafontaine. 1997-08-26. Scaling and the Metal-Insulator Transition in Si/SiGe Quantum Wells. https://doi.org/10.1103/physrevb.56.r12741

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