Adiabatic quantum pumping in an Aharonov-Bohm loop and in a Si-like nanowire: Role of interference in real space and in momentum space

Abstract

We study the consequences of interference effects on the current generated by adiabatic quantum pumping in two distinct one-dimensional (1D) lattice model. The first model contains an Aharonov-Bohm (AB) loop within a tight-binding chain of lattice sites. The static AB phase is shown to strongly affect interference between the two arms of the loop, serving as an on-off switch and regulator for the pumped current. The second model simulates pumping in semiconductors with indirect band-gaps, by utilizing a tight-binding chain with next-nearest-neighbor coupling. The model exhibits signatures of interference between degenerate conduction band states with different Fermi wavevectors.