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Fractionalized Fermi liquids

T. Senthil·Subir Sachdev·Matthias Vojta
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Abstract

In spatial dimensions d >= 2, Kondo lattice models of conduction and local moment electrons can exhibit a fractionalized, non-magnetic state (FL*) with a Fermi surface of sharp electron-like quasiparticles, enclosing a volume quantized by (ρ_a-1)(mod 2), with ρ_a the mean number of all electrons per unit cell of the ground state. Such states have fractionalized excitations linked to the deconfined phase of a gauge theory. Confinement leads to a conventional Fermi liquid state, with a Fermi volume quantized by ρ_a (mod 2), and an intermediate superconducting state for the Z_2 gauge case. The FL* state permits a second order metamagnetic transition in an applied magnetic field.

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T. Senthil, Subir Sachdev, Matthias Vojta. 2003-05-07. Fractionalized Fermi liquids. https://doi.org/10.1103/physrevlett.90.216403

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