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arXiv · 0912.0943

Effective theory of Fermi pockets in fluctuating antiferromagnets

Yang Qi·Subir Sachdev
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Abstract

We describe fluctuating two-dimensional metallic antiferromagnets by transforming to a rotating reference frame in which the electron spin polarization is measured by its projections along the local antiferromagnetic order. This leads to a gauge-theoretic description of an `algebraic charge liquid' involving spinless fermions and a spin S=1/2 complex scalar. We propose a phenomenological effective lattice Hamiltonian which describes the binding of these particles into gauge-neutral, electron-like excitations, and describe its implications for the electron spectral function across the entire Brillouin zone. We discuss connections of our results to photoemission experiments in the pseudogap regime of the cuprate superconductors.

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Yang Qi, Subir Sachdev. 2010-03-01. Effective theory of Fermi pockets in fluctuating antiferromagnets. https://doi.org/10.1103/physrevb.81.115129

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