An ideal rapid-cycle Thouless pump

TL;DR

This paper introduces a family of finite-frequency protocols for the Rice-Mele model that achieve perfect quantized charge pumping without excitations, overcoming adiabaticity limitations in Thouless pumping.

Contribution

It presents a novel family of protocols ensuring quantized charge transport at finite frequencies, derived from a mapping to the Euclidean sinh-Gordon equation.

Findings

Achieves quantized charge pumping at finite frequencies.

Ensures absence of excitations during the cycle.

Includes an adiabatic protocol as a special case.

Abstract

Thouless pumping is a fundamental instance of quantized transport, which is topologically protected. Although its theoretical importance, the adiabaticity condition is an obstacle for further practical applications. Here, focusing on the Rice-Mele model, we provide a family of finite-frequency examples that ensure both the absence of excitations and the perfect quantization of the pumped charge at the end of each cycle. This family, which contains an adiabatic protocol as a limiting case, is obtained through a mapping onto the zero curvature representation of the Euclidean sinh-Gordon equation.