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arXiv · 2211.16296

Spin-liquid insulators can be Landau's Fermi liquids

Michele Fabrizio
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Abstract

The long search for insulating materials that possess low-energy quasiparticles carrying electron's quantum numbers except charge - inspired by the neutral spin-1/2 excitations, the so-called spinons, exhibited by Anderson's resonating-valence-bond state - seems to have reached a turning point after the discovery of several Mott insulators displaying same thermal and magnetic properties as metals, including quantum oscillations in a magnetic field. Here, we show that such anomalous behaviour is not inconsistent with Landau's Fermi liquid theory of quasiparticles at a Luttinger surface. That is the manifold of zeros within the Brillouin zone of the single-particle Green's function at zero frequency, and which thus defines the spinon Fermi surface conjectured by Anderson.

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Michele Fabrizio. 2022-11-29. Spin-liquid insulators can be Landau's Fermi liquids. https://doi.org/10.1103/physrevlett.130.156702

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