Phenomenology of the 0.7 Conductance Feature
نویسندگان
چکیده
We describe a phenomenological model for the conductance feature near 0.7 × 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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