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arXiv · 1411.7574

Interplay between condensation energy, pseudogap and the specific heat of a Hubbard model in a n-pole approximation

A. C. Lausmann·E. J. Calegari·S. G. Magalhaes·C. M. Chaves·A. Troper
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Abstract

The condensation energy and the specific heat jump of a two-dimensional Hubbard model, suitable to discuss high-$T_c$ superconductors, is studied. In this work, the Hubbard model is investigated by the Green's function method within a $n$-pole approximation, which allows to consider superconductivity with $d_{x^2-y^2}$-wave pairing. In the present scenario, the pseudogap regime emerges when the antiferromagnetic (AF) correlations become sufficiently strong to move to lower energies the region around of the nodal point $(π,π)$ on the renormalized bands. It is observed that above a given total occupation $n_T$, the specific heat jump $ΔC$ and also the condensation energy $U(0)$ decrease signaling the presence of the pseudogap.

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A. C. Lausmann, E. J. Calegari, S. G. Magalhaes, C. M. Chaves, A. Troper. 2014-11-27. Interplay between condensation energy, pseudogap and the specific heat of a Hubbard model in a n-pole approximation. https://doi.org/10.1007/s10909-014-1259-5

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