Quantum inductance and negative electrochemical capacitance at finite frequency

J. Wang; B. G. Wang; H. Guo

doi:10.1103/physrevb.75.155336

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arXiv · cond-mat/0701360

Quantum inductance and negative electrochemical capacitance at finite frequency

J. Wang·B. G. Wang·H. Guo

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Abstract

We report on theoretical investigations of frequency dependent quantum capacitance. It is found that at finite frequency a quantum capacitor can be characterized by a classical RLC circuit with three parameters: a static electrochemical capacitance, a charge relaxation resistance, and a quantum inductance. The quantum inductance is proportional to the characteristic time scale of electron dynamics and due to its existence, the time dependent current can accumulate a phase delay and becomes lagging behind the applied ac voltage, leading to a negative effective capacitance.

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J. Wang, B. G. Wang, H. Guo. 2007-01-16. Quantum inductance and negative electrochemical capacitance at finite frequency. https://doi.org/10.1103/physrevb.75.155336

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