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Adiabatic charge pumping through a dot at the junction of N quantum wires

Shamik Banerjee·Anamitra Mukherjee·Sumathi Rao·Arijit Saha
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Abstract

We study adiabatic charge pumping through a quantum dot placed at the junction of $N$ quantum wires. We explicitly map out the pattern of pumped charge as a function of the time-varying tunneling parameters coupling the wires to the dot and the phase between any two time varying parameters controlling the shape of the dot. We find that with $N-2$ time-independent well-coupled leads, the maximum pumped charge in the remaining two leads is strongly suppressed with increasing $N$, leading to the possibility of tuning of the pumped charge, by modulating the coupling of the $N-2$ leads.

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Shamik Banerjee, Anamitra Mukherjee, Sumathi Rao, Arijit Saha. 2007-03-09. Adiabatic charge pumping through a dot at the junction of N quantum wires. https://doi.org/10.1103/physrevb.75.153407

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