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Photon-Assisted Transport Through Ultrasmall Quantum Dots: Influence of Intradot Transitions

Ph. Brune·C. Bruder·H. Schoeller
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Abstract

We study transport through one or two ultrasmall quantum dots with discrete energy levels to which a time-dependent field is applied (e.g., microwaves). The AC field causes photon-assisted tunneling and also transitions between discrete energy levels of the dot. We treat the problem by introducing a generalization of the rotating-wave approximation to arbitrarily many levels. We calculate the dc-current through one dot and find satisfactory agreement with recent experiments by Oosterkamp et al. . In addition, we propose a novel electron pump consisting of two serially coupled single-level quantum dots with a time-dependent interdot barrier.

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Ph. Brune, C. Bruder, H. Schoeller. 1997-03-25. Photon-Assisted Transport Through Ultrasmall Quantum Dots: Influence of Intradot Transitions. https://doi.org/10.1103/physrevb.56.4730

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