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arXiv · 2607.19470

Coloring in anyon superconductivity

Abstract

The recently observed signatures of superconductivity proximate to a fractional quantum anomalous Hall (FQAH) state in a twisted MoTe$_2$ bilayer has revitalized interest in quantum phases of matter induced by anyon dynamics. Here we show how a panoply of anyon-driven phases associated with doping the lattice ${ν=2/3}$ FQAH state can be realized as competing instabilities of a Fermi surface of charge-$e/3$ ``quarks'' coupled to a $\mathrm{SU}(3)_{-1}$ Chern-Simons gauge field, which is dual to the more conventional $\mathrm{U}(1)_3$ Chern-Simons-Ginzburg-Landau theory of quasiholes. For example, a range of electronic superconductors emerge from \emph{color superconductivity}, under which the Fermi surface experiences a pairing instability mediated by gauge fluctuations. These include SC$\star$ phases -- where superconductivity coexists with topological order -- as well as topological superconductors displaying half-integer chiral central charges when the quarks are weakly paired. One example is a $p+ip$ ``color-valley-locked'' superconductor, a topological analogue of the color superconductor familiar in quantum chromodynamics. On the other hand, both superconducting and non-Fermi liquid phases can emerge when the quarks form an itinerant ferromagnet, polarizing the Fermi surface to a particular combination of colors. Finally, our framework naturally accommodates the possibility of anyonic bound state formation, allowing access to phases induced by doping anyons of charge $2e/3$ as opposed to $e/3$ within the same model. Our work unifies many earlier proposed anyonic phases as instabilities of a single parent \emph{quark metal} phase, distilling their emergence into a competition between superconductivity and itinerant color ferromagnetism.

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BibTeXRIS

Umang Mehta, Yuto Nakajima, Hart Goldman. 2026-07-29. Coloring in anyon superconductivity. https://arxiv.org/abs/2607.19470

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