Fast counter-diabatic Thouless pumping in the Rice-Mele mode

Abstract: Thouless pumping is a transport phenomenon where a periodically varying Hamiltonian can transfer a quantized amount of charge when the time-dependence of the Hamiltonian is quasi-adiabatic. Past proposals to speed up this process involving Floquet techniques lead to a subtle problem of setting the initial state of the system. In this work we apply counter-diabatic driving to the Rice-Mele model, which is one of the simplest models for Thouless pumping, to ensure that the system remains in the ground state for any driving speed. We show that the pumped charge across each bond of the Rice-Mele model is given by a topologically quantized Chern number in this case. However, the counter-diabatic driving in a general case turns out to involve long-range hopping. We show that this can be mitigated either by choosing a very specific example of the Rice-Mele model or by numerical optimization of the Hamiltonian to create experimentally realizable variants of fast pumping in the Rice-Mele model.