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Analysis of the Metallic Phase of Two-Dimensional Holes in SiGe in Terms of Temperature Dependent Screening

V. Senz·T. Ihn·T. Heinzel·K. Ensslin·G. Dehlinger·D. Grutzmacher·U. Gennser
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Abstract

We find that temperature dependent screening can quantitatively explain the metallic behaviour of the resistivity on the metallic side of the so-called metal-insulator transition in p-SiGe. Interference and interaction effects exhibit the usual insulating behaviour which is expected to overpower the metallic background at sufficiently low temperatures. We find empirically that the concept of a Fermi-liquid describes our data in spite of the large r_s = 8.

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V. Senz, T. Ihn, T. Heinzel, K. Ensslin, G. Dehlinger, D. Grutzmacher, U. Gennser. 2000-04-27. Analysis of the Metallic Phase of Two-Dimensional Holes in SiGe in Terms of Temperature Dependent Screening. https://doi.org/10.1103/physrevlett.85.4357

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