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Spectral properties and pseudogaps in a model with d-wave pairing symmetry

Bumsoo Kyung
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Abstract

A model with d-wave pairing symmetry is studied by employing a non-perturbative sum rule approach. At low temperature the magnitude of a normal state pseudogap shows strong $\vec{k}$ or angle dependence well fitted by $\cos 2ϕ$ form. With increasing temperature, the pseudogap closes at some critical angle $ϕ_{c}$ and beyond this angle a single quasiparticle-like peak appears. The resulting Fermi surface is strongly temperature dependent. Both in the spectral function and the density of states, the pseudogap disappears in a manner that the spectral weight fills in the pseudogap instead of closing it with increasing temperature. All these features are qualitatively consistent with ARPES for underdoped cuprates.

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Bumsoo Kyung. 2000-09-25. Spectral properties and pseudogaps in a model with d-wave pairing symmetry. https://doi.org/10.1103/physrevb.63.014502

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