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Analysis of the temperature-dependent quantum point contact conductance in view of the metal-insulator transition in two dimensions

V. Senz·T. Heinzel·T. Ihn·S. Lindemann·R. Held·K. Ensslin·W. Wegscheider·M. Bichler
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Abstract

The temperature dependence of the conductance of a quantum point contact has been measured. The conductance as a function of the Fermi energy shows temperature-independent fixed points, located at roughly multiple integers of $e^{2}/h$. Around the first fixed point at e$^{2}$/h, the experimental data for different temperatures can been scaled onto a single curve. For pure thermal smearing of the conductance steps, a scaling parameter of one is expected. The measured scaling parameter, however, is significantly larger than 1. The deviations are interpreted as a signature of the potential landscape of the quantum point contact, and of the source-drain bias voltage. We relate our results phenomenologically to the metal-insulator transition in two dimensions.

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V. Senz, T. Heinzel, T. Ihn, S. Lindemann, R. Held, K. Ensslin, W. Wegscheider, M. Bichler. 2000-12-13. Analysis of the temperature-dependent quantum point contact conductance in view of the metal-insulator transition in two dimensions. https://doi.org/10.1088/0953-8984%2F13%2F17%2F303

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