Thermal ionization of impurity-bound quasiholes in the fractional quantum Hall effect

Ke Huang; Sankar Das Sarma; Xiao Li

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arXiv · 2512.07769

Thermal ionization of impurity-bound quasiholes in the fractional quantum Hall effect

Ke Huang·Sankar Das Sarma·Xiao Li

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Abstract

We study the interplay between a Coulomb impurity and quasiholes in a fractional quantum Hall (FQH) state at finite temperatures. While a repulsive impurity can pin a quasihole and stabilize the FQH state, an attractive impurity cannot bind quasiholes. We demonstrate that at finite temperatures, a quasihole can be thermally ionized from a repulsive impurity, resulting in an ionization phase transition. We propose an experimental setup using exciton sensing to detect such a thermal ionization of quasiholes.

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Ke Huang, Sankar Das Sarma, Xiao Li. 2025-12-08. Thermal ionization of impurity-bound quasiholes in the fractional quantum Hall effect. https://arxiv.org/abs/2512.07769

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