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arXiv · 2609.17116

Thouless pumping via discrete jumping of the adiabatic Hamiltonian

Abstract

Thouless pumping is a celebrated topological effect that enables quantized particle transport and holds promise for applications in quantum technologies. However, the standard adiabatic pumping theory dictate that the Hamiltonian must be varied continuously and slowly throughout the whole pumping process. In this work, we show that Thouless pumping can be realized by using only discrete sampling of the Hamiltonian, removing the conventional constraint of continuous and slow change of control. Specifically, we select particular parameter points of the Hamiltonian for conventional continuous quantum adiabatic evolution, and then apply the Hamiltonian at these parameter points which induces a geodesic evolution for the pseudospin with a given quasimomentum. This realizes an adiabatic evolution for the Thouless pumping according to a necessary and sufficient condition for quantum adiabatic evolution.

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Lang Yu, Yihan Wu, Zhen-Yu Wang. 2026-09-15. Thouless pumping via discrete jumping of the adiabatic Hamiltonian. https://arxiv.org/abs/2609.17116

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