Nonadiabatic Control of Geometric Pumping

TL;DR

This paper investigates nonadiabatic effects in geometric pumping, providing exact current calculations, a unified geometric interpretation across frequency regimes, and methods to enhance current via shortcuts to adiabaticity.

Contribution

It offers an exact solution for nonadiabatic geometric pumping current and connects adiabatic and Floquet theories, introducing control techniques to optimize the current.

Findings

Exact nonadiabatic pumping current derived.

Unified geometric interpretation across frequency regimes.

Shortcut to adiabaticity enhances pumping current.

Abstract

We study nonadiabatic effects of geometric pumping. With arbitrary choices of periodic control parameters, we go beyond the adiabatic approximation to obtain the exact pumping current. We find that a geometrical interpretation for the nontrivial part of the current is possible even in the nonadiabatic regime. The exact result allows us to find a smooth connection between the adiabatic Berry phase theory at low frequencies and the Floquet theory at high frequencies. We also study how to control the geometric current. Using the method of shortcuts to adiabaticity with the aid of an assisting field, we illustrate that it enhances the current.