Is the fractional Chern insulator-superconductor transition in twisted MoTe$_2$ direct?

Tevž Lotrič; Steven H. Simon

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arXiv · 2609.30368

Is the fractional Chern insulator-superconductor transition in twisted MoTe$_2$ direct?

Tevž Lotrič·Steven H. Simon

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Abstract

The observation of superconducting behaviour near a fractional Chern insulator in twisted MoTe$_2$ has sparked excitement about a possible direct "anyon superconducting" transition between a topologically ordered and a symmetry-broken phase. We carefully examine the experimentally measured transport data in the relevant region of the low-temperature tMoTe$_2$ phase diagram and propose a scenario where the nearby reentrant integer quantum Hall effect (RIQHE) acts as an intervening phase between the two. While the RIQHE is most prominent at large displacement fields, we propose that it extends to smaller fields at very low temperatures. Based on this picture, we model the sample as a patchwork of the three phases and show that such a model can explain the main qualitative features of the transport phase diagram, including its dependence on temperature and displacement field. The model predicts that at lower electronic temperatures the apparent FCI-SC transition at zero displacement field should split into two transitions separated by a narrow RIQHE region.

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Tevž Lotrič, Steven H. Simon. 2026-09-24. Is the fractional Chern insulator-superconductor transition in twisted MoTe$_2$ direct?. https://arxiv.org/abs/2609.30368

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