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arXiv · 2504.09338

Multi-band fractional Thouless pumps

Marius Jürgensen·Jacob Steiner·Gil Refael·Mikael C. Rechtsman
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Abstract

Quantization of particle transport lies at the heart of topological physics. In Thouless pumps - dimensionally reduced versions of the integer quantum Hall effect - quantization is dictated by the integer winding of single-band Wannier states. Here, we show that repulsive interactions can drive a transition from an integer- to a fractional-quantized Thouless pump (at fixed integer filling) by stabilizing a crystal of multi-band Wannier states, each with fractional winding. We numerically illustrate the concept in few-particle systems, and show that a dynamical Hartree-Fock ansatz can quantitatively reproduce the pumping phase diagram.

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Marius Jürgensen, Jacob Steiner, Gil Refael, Mikael C. Rechtsman. 2025-04-12. Multi-band fractional Thouless pumps. https://arxiv.org/abs/2504.09338

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