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arXiv · 0909.0367

Quantum pumping in deformable quantum dots

F. Romeo·R. Citro
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Abstract

The charge current pumped adiabatically through a deformable quantum dot is studied within the Green's function approach. Differently from the non-deformable case, the current shows an undefined parity with respect to the pumping phase ϕ. The unconventional current-phase relation, analyzed in the weak pumping regime, is due to a dynamical phase shift ϕ_D caused by the elastic deformations of the central region (classical phonons). The role of the quality factor Q of the oscillator, the effects induced by a mechanical resonance and the implications for current experiments on molecular systems are also discussed.

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F. Romeo, R. Citro. 2009-09-02. Quantum pumping in deformable quantum dots. https://doi.org/10.1103/physrevb.80.235328

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