2026/07/30 by Pavel A. Nosov, Zhengyan Darius Shi
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.stat-mech #cond-mat.str-el
21 pages, 6 figures, 10 page appendix
We study transport in lattice composite Fermi liquids realized in half-filled Chern bands with broken inversion symmetry. We show that reduced crystalline symmetry exposes intrinsic singular dynamical responses of composite fermions that are otherwise hidden in the conventional Landau-level setting. At zero wave vector, inversion breaking allows gauge-field fluctuations to generate a non-analytic longitudinal optical resistivity, with Reρxx(ω)∼ |ω|4/3 for gate-screened Coulomb interactions. At finite wave vector q, inversion breaking leads to nonreciprocal transport and a non-analytic ∼ |q| dependence of the Hall conductivity, both of which can be probed through surface acoustic wave propagation. We also discuss a distinct mechanism for singular DC transport in lattice composite Fermi liquids: renormalization of 2kF scattering at the composite Fermi surface enhances Umklapp relaxation and can lead to a non-analytic temperature dependence of the resistivity. Taken together, our results identify transport signatures of lattice composite Fermi liquids that are absent in their continuum quantum Hall counterparts and can be directly tested in ongoing experiments on twisted MoTe2 and rhombohedral graphene, where evidence for zero-field composite Fermi liquids has recently been reported.