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Phenomenology of the 0.7 conductance feature

D. J. Reilly·Y. Zhang·L. DiCarlo
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Abstract

We describe a phenomenological model for the conductance feature near $0.7 \times 2e^2/h$ that occurs in quantum point contacts. We focus on the transconductance at finite source-drain bias and contrast our model with the results expected from a single-particle picture. Good agreement is seen in comparing the model with experimental data, taken on ultra-low-disorder GaAs induced electron systems. Although simple, our phenomenology suggests important boundary conditions for an underlying microscopic theory.

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D. J. Reilly, Y. Zhang, L. DiCarlo. 2006-01-07. Phenomenology of the 0.7 conductance feature. https://doi.org/10.1016/j.physe.2006.02.027

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