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arXiv · 1405.3845

Single-electron approach for time-dependent electron transport

Shmuel Gurvitz
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Abstract

We develop a new approach to electron transport in mesoscopic systems by using a particular single-particle basis. Although this basis generates redundant many-particle amplitudes, it greatly simplifies the treatment. By using our method for transport of non-interacting electrons, we generalize the Landauer formula for transient currents and for time-dependent potentials. The result has a very simple form and clear physical interpretation. As an example, we apply it to resonant tunneling through a quantum dot where the tunneling barriers are oscillating in time. We obtain analytical expression for the time-dependent (ac) resonant current. However, in the adiabatic limit this expression displays the dc current for zero bias (electron pumping).

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Shmuel Gurvitz. 2015-10-12. Single-electron approach for time-dependent electron transport. https://doi.org/10.1088/0031-8949%2F2015%2Ft165%2F014013

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