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The relaxation time of a chiral quantum R-L circuit

Julien Gabelli·Gwendal Fève·Takis Kontos·Jean-Marc Berroir·Bernard Plaçais·Christian Glattli·Bernard Etienne·Yong Jin·Markus Büttiker
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Abstract

We report on the GHz complex admittance of a chiral one dimensional ballistic conductor formed by edge states in the quantum Hall regime. The circuit consists of a wide Hall bar (the inductor L) in series with a tunable resistor (R) formed by a quantum point contact. Electron interactions between edges are screened by a pair of side gates. Conductance steps are observed on both real and imaginary parts of the admittance. Remarkably, the phase of the admittance is transmission-independent. This shows that the relaxation time of a chiral R-L circuit is resistance independent. A current and charge conserving scattering theory is presented that accounts for this observation with a relaxation time given by the electronic transit time in the c cuit.

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Julien Gabelli, Gwendal Fève, Takis Kontos, Jean-Marc Berroir, Bernard Plaçais, Christian Glattli, Bernard Etienne, Yong Jin, Markus Büttiker. 2007-05-14. The relaxation time of a chiral quantum R-L circuit. https://doi.org/10.1103/physrevlett.98.166806

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