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An Approximate Sign Sum Rule for the Transmission Amplitude Through a Quantum Dot

Reinhard Baltin·Yuval Gefen
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Abstract

We study the phase of the transmission amplitude through a disordered quantum dot in the Coulomb blockade regime. We calculate the phase dependence on gate voltage for a disorder configuration. We show that over a ``period'', consisting of a resonance and a transmission valley, the total phase change is 0 (mod $2π$). Deviations from this sum rule are small in the parameter (level spacing/charging energy). The disorder-averaged phase-phase correlation function is found showing interaction-induced correlations between phases at different gate voltages.

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Reinhard Baltin, Yuval Gefen. 1999-07-14. An Approximate Sign Sum Rule for the Transmission Amplitude Through a Quantum Dot. https://doi.org/10.1103/physrevlett.83.5094

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