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Pressure and high-T-c superconductivity in sulfur hydrides

Title: Pressure and high-T-c superconductivity in sulfur hydrides.
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Name(s): Gor'kov, Lev P., author
Kresin, Vladimir Z., author
Type of Resource: text
Genre: Text
Date Issued: 2016-05-11
Physical Form: computer
online resource
Extent: 1 online resource
Language(s): English
Abstract/Description: The paper discusses fundamentals of record-T-C superconductivity discovered under high pressure in sulfur hydride. The rapid increase of T-C with pressure in the vicinity of P-cr approximate to 123GPa is interpreted as the fingerprint of a first-order structural transition. Based on the cubic symmetry of the high-T-C phase, it is argued that the lower-T-C phase has a different periodicity, possibly related to an instability with a commensurate structural vector. In addition to the acoustic branches, the phonon spectrum of H3S contains hydrogen modes with much higher frequencies. Because of the complex spectrum, usual methods of calculating T-C are here inapplicable. A modified approach is formulated and shown to provide realistic values for T-C and to determine the relative contributions of optical and acoustic branches. The isotope effect ( change of T-C upon Deuterium for Hydrogen substitution) originates from high frequency phonons and differs in the two phases. The decrease of T-C following its maximum in the high-T-C phase is a sign of intermixing with pairing at hole-like pockets which arise in the energy spectrum of the cubic phase at the structural transition. On-pockets pairing leads to the appearance of a second gap and is remarkable for its non-adiabatic regime: hydrogen mode frequencies are comparable to the Fermi energy.
Identifier: FSU_libsubv1_wos_000375757500001 (IID), 10.1038/srep25608 (DOI)
Keywords: electrons, hydrogen, lattice-vibrations, metal, strong-coupled superconductors, system, transition-temperature
Publication Note: The publisher’s version of record is available at http://www.dx.doi.org/10.1038/srep25608
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_libsubv1_wos_000375757500001
Owner Institution: FSU
Is Part Of: Scientific Reports.
2045-2322
Issue: vol. 6

Choose the citation style.
Gor'kov, L. P., & Kresin, V. Z. (2016). Pressure and high-T-c superconductivity in sulfur hydrides. Scientific Reports. Retrieved from http://purl.flvc.org/fsu/fd/FSU_libsubv1_wos_000375757500001