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

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.