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arXiv · 1206.2573

Superradiance-like Electron Transport through a Quantum Dot

Martin J. A. Schuetz·Eric M. Kessler·J. Ignacio Cirac·Geza Giedke
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Abstract

We theoretically show that intriguing features of coherent many-body physics can be observed in electron transport through a quantum dot (QD). We first derive a master equation based framework for electron transport in the Coulomb-blockade regime which includes hyperfine (HF) interaction with the nuclear spin ensemble in the QD. This general tool is then used to study the leakage current through a single QD in a transport setting. We find that, for an initially polarized nuclear system, the proposed setup leads to a strong current peak, in close analogy with superradiant emission of photons from atomic ensembles. This effect could be observed with realistic experimental parameters and would provide clear evidence of coherent HF dynamics of nuclear spin ensembles in QDs.

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Martin J. A. Schuetz, Eric M. Kessler, J. Ignacio Cirac, Geza Giedke. 2012-06-12. Superradiance-like Electron Transport through a Quantum Dot. https://doi.org/10.1103/physrevb.86.085322

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