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arXiv · 2402.02532

Common behavior of the scaled condensation energy for both high-$T_c$ and conventional superconductors

V. R. Shaginyan·A. Z. Msezane·S. A. Artamonov
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Abstract

We analyze the scaling of the condensation energy $E_Δ$ divided by $γ$, $E_Δ/γ\simeq N(0)Δ_1^2/γ$, of both conventional superconductors and unconventional high-$T_c$ one, where $N(0)$ is the density of states, $Δ_1$ is the maximum value of the superconducting gap and $γ$ is the Sommerfeld coefficient. For the first time, we show that the universal scaling of $E_Δ/γ\propto T_c^2$ applies equally to conventional superconductors and unconventional high-$T_c$ ones. Our consideration is based on both facts: Bogoliubov quasiparticles act in conventional and unconventional superconductors, and the corresponding flat band is deformed by the unconventional superconducting state. As a result, our theoretical observations based on the fermion condensation theory are in good agreement with experimental facts.

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V. R. Shaginyan, A. Z. Msezane, S. A. Artamonov. 2024-04-21. Common behavior of the scaled condensation energy for both high-$T_c$ and conventional superconductors. https://doi.org/10.3390/cryst14090826

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