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arXiv · cond-mat/0405383

Tunable Fermi-Edge Resonance in an Open Quantum Dot

D. A. Abanin·L. S. Levitov
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Abstract

Resonant tunneling in an open mesoscopic quantum dot is proposed as a vehicle to realize a tunable Fermi-edge resonance with variable coupling strength. We solve the x-ray edge problem for a generic nonseparable scatterer and apply it to describe tunneling in a quantum dot. The tunneling current power law exponent is linked to the S-matrix of the dot. The control of scattering by varying the dot shape and coupling to the leads allows to explore a wide range of exponents. Transport properties, such as weak localization, mesoscopic conductance fluctuations, and sensitivity to Wigner-Dyson ensemble type, have their replicas in the Fermi-edge singularity.

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D. A. Abanin, L. S. Levitov. 2004-05-20. Tunable Fermi-Edge Resonance in an Open Quantum Dot. https://doi.org/10.1103/physrevlett.93.126802

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