Kondo breakdown transition in a gate-tuned moire Kondo lattice

In $\mathrm{MoTe_2}$/$\mathrm{WSe_2}$ heterobilayers with the $\mathrm{MoTe_2}$ moire band at filling $\nu_f = 1$ (local moments) and the $\mathrm{WSe_2}$ band doped to density $n_c$ per moire cell, Zhao et al. (Nature, 2023, arXiv:2211.00263) reported a heavy Fermi liquid with a large Fermi surface and gate-tunable Kondo temperature, destroyed by magnetic field. Determine whether reducing the Kondo coupling by displacement field or field produces a Kondo-breakdown transition at which the Fermi-surface volume jumps from $\nu_f + n_c$ to $n_c$ per moire cell, whether it is continuous, and whether it coincides with magnetic order of the moments. An answer is the Hall number and quasiparticle mass across the transition at $T \to 0$ and the magnetic state on each side.

Hall-number and quantum-oscillation measurements across the tuned transition at the lowest temperatures, with magnetic circular dichroism tracking the order of the local moments.