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arXiv · 0909.2778

Non-adiabatic pumping of single electrons affected by magnetic fields

Christoph Leicht·Bernd Kaestner·Vyacheslavs Kashcheyevs·Philipp Mirovsky·Thomas Weimann·Klaus Pierz·Hans-Werner Schumacher
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Abstract

Non-adiabatic pumping of discrete charges, realized by a dynamical quantum dot in an AlGaAs/GaAs heterostructure, is studied under influence of a perpendicular magnetic field. Application of an oscillating voltage in the GHz-range to one of two top gates, crossing a narrow wire and confining a quantum dot, leads to quantized pumped current plateaus in the gate characteristics. The regime of pumping one single electron is traced back to the diverse tunneling processes into and out-of the dot. Extending the theory to multiple electrons allows to investigate conveniently the pumping characteristics in an applied magnetic field. In this way, a qualitatively different behavior between pumping even or odd numbers of electrons is extracted.

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Christoph Leicht, Bernd Kaestner, Vyacheslavs Kashcheyevs, Philipp Mirovsky, Thomas Weimann, Klaus Pierz, Hans-Werner Schumacher. 2009-09-15. Non-adiabatic pumping of single electrons affected by magnetic fields. https://doi.org/10.1016/j.physe.2009.11.109

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