Fractionalized metals from doped anyons: Application to tMoTe2

Abstract

A fluid of mobile anyons may arise naturally when a Fractional Quantum Anomalous Hall (FQAH) state is doped. Motivated by recent experiments on twisted $MoTe_2$, we study metallic phases obtained by doping the $σ_{xy} = 2e^2/3h$ state. We propose that the high-resistivity metal observed adjacent to this FQAH state is a $Z_3$ Orthogonal Metal: a non-Fermi liquid with sharp charge $1/3$ fermionic quasiparticles coupled to a discrete $Z_3$ gauge field but with no sharp electronic quasiparticle. For a dilute gas of three species of charge-$1/3$ anyons with $π/3$ statistics, we construct two $U(3)$ symmetric $Z_3$ Orthogonal Metals, distinguished by whether the gapless fermions transform as $SU(3)$ triplets or singlets. We show that these states naturally yield large electrical resistivities even when the fractionalized quasiparticles are in a good metallic regime. Pairing of the charge-$1/3$ fermions produces an ordinary charge-$2e$ superconductor, smoothly connected to a BCS state but obtained through an intrinsically fractionalized normal state. We discuss experimental signatures of the idea that the normal metallic state in the lightly doped $2/3$ state may have fractionalized charge carriers.