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تسجيل مستخدم جديدResonant multigap superconductivity at room temperature near a Lifshitz topological transition in sulphur hydrides
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The maximum critical temperature for superconductivity in pressurized hydrides appears at the top of superconducting domes in Tc versus pressure curves at a particular pressure, which is not predicted by standard superconductivity theories. Filling this gap we propose first-principles quantum calculation of a universal superconducting dome where Tc amplification in multigap superconductivity is driven by the Fano-Feshbach resonance due to configuration interaction between open and closed pairing channels, i.e., between multiple gaps in the BCS regime, resonating with a single gap in the BCS-BEC crossover regime. We focus on the a high-order anisotropic van Hove singularity near the Fermi level observed in band structure calculations of pressurized sulfur hydride, typical of a supermetal, associated with the array of metallic hydrogen wires modules forming a nanoscale heterostructure at atomic limit called superstripes phase. In the proposed three dimensional (3D) phase diagram the critical temperature shows a superconducting dome where Tc is a function of two variables (i) the Lifshitz parameter, eta, measuring the separation of the chemical potential from the Lifshitz transition normalized by the inter-wires coupling and (ii) the effective electron phonon coupling (g) in the appearing new Fermi surface including phonon softening. The results will be of help for material design of room temperature superconductors at ambient pressure.
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