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arXiv · cond-mat/9601074

Low frequency admittance of a quantum point contact

T. Christen·M. Buttiker
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Abstract

We present a current and charge conserving theory for the low frequency admittance of a quantum point contact. We derive expressions for the electrochemical capacitance and the displacement current. The latter is determined by the {\em emittance} which equals the capacitance only in the limit of vanishing transmission. With the opening of channels the capacitance and the emittance decrease in a step-like manner in synchronism with the conductance steps. For vanishing reflection, the capacitance vanishes and the emittance is negative.

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T. Christen, M. Buttiker. 1996-01-18. Low frequency admittance of a quantum point contact. https://doi.org/10.1103/physrevlett.77.143

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