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Moments of the ARPES spectral function of an undoped Mott insulator

Vadim Oganesyan
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Abstract

We derive analytic expressions for the first three frequency moments of the single particle spectral function for one hole in a Mott insulator in terms of equilibrium spin correlation functions of the insulating state. We show that the ``remnant Fermi surface`` detected in ARPES experiments is, in fact, a reflection of the strong antiferromagnetic correlations of the system, {\it not} a reflection of the original band-structure Fermi surface. We suggest that ARPES data could be used to measure the magnetic specific heat.

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Vadim Oganesyan. 2000-03-15. Moments of the ARPES spectral function of an undoped Mott insulator. https://arxiv.org/abs/cond-mat/0003270

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