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Quantum dimer model for the pseudogap metal.

ABSTRACT: We propose a quantum dimer model for the metallic state of the hole-doped cuprates at low hole density, p. The Hilbert space is spanned by spinless, neutral, bosonic dimers and spin S = 1/2, charge +e fermionic dimers. The model realizes a "fractionalized Fermi liquid" with no symmetry breaking and small hole pocket Fermi surfaces enclosing a total area determined by p. Exact diagonalization, on lattices of sizes up to 8 × 8, shows anisotropic quasiparticle residue around the pocket Fermi surfaces. We discuss the relationship to experiments.

SUBMITTER: Punk M

PROVIDER: S-EPMC4534260 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Quantum dimer model for the pseudogap metal.

Punk Matthias M Allais Andrea A Sachdev Subir S

Proceedings of the National Academy of Sciences of the United States of America 20150720 31

We propose a quantum dimer model for the metallic state of the hole-doped cuprates at low hole density, p. The Hilbert space is spanned by spinless, neutral, bosonic dimers and spin S = 1/2, charge +e fermionic dimers. The model realizes a "fractionalized Fermi liquid" with no symmetry breaking and small hole pocket Fermi surfaces enclosing a total area determined by p. Exact diagonalization, on lattices of sizes up to 8 × 8, shows anisotropic quasiparticle residue around the pocket Fermi surfac ...[more]

PMID: 26195771

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