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arXiv · 1012.4663

Optimization of electron pumping by harmonic mixing

Niklas Rohling·Frank Grossmann
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Abstract

For a symmetric bridge coupled to infinite leads, in the presence of a dipole-coupled external ac-field with harmonic mixing, we solve the Schrödinger equation in the time-domain using open boundary conditions as well as in the energy-domain using Floquet scattering theory. As this potential breaks parity and generalized parity, we find a non-vanishing average current. We then optimize the relative amplitude ratio between the fundamental and the second harmonic leading to a maximum in the pump current.

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Niklas Rohling, Frank Grossmann. 2011-03-22. Optimization of electron pumping by harmonic mixing. https://doi.org/10.1103/physrevb.83.205310

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