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Transmission Phase Shift of a Quantum Dot with Kondo Correlations

Ulrich Gerland·Jan von Delft·Theo Costi·Yuval Oreg
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Abstract

We study the effects of Kondo correlations on the transmission phase shift of a quantum dot in an Aharonov-Bohm ring. We predict in detail how the development of a Kondo resonance should affect the dependence of the phase shift on transport voltage, gate voltage and temperature. This system should allow the first direct observation of the well-known scattering phase shift of pi/2 expected (but not directly measurable in bulk systems) at zero temperature for an electron scattering off a spin-1/2 impurity that is screened into a singlet.

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Ulrich Gerland, Jan von Delft, Theo Costi, Yuval Oreg. 2000-04-26. Transmission Phase Shift of a Quantum Dot with Kondo Correlations. https://doi.org/10.1103/physrevlett.84.3710

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