Causes of high-temperature superconductivity in the hydrogen sulfide electron-phonon system

Nikolay Degtyarenko; Evgeny Mazur

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arXiv · 1507.05749

Causes of high-temperature superconductivity in the hydrogen sulfide electron-phonon system

Nikolay Degtyarenko·Evgeny Mazur

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Abstract

The electron and phonon spectra, as well as the density of electron and phonon states of the stable orthorhombic structure of hydrogen sulfide (SH2) at pressures 100-180 GPa have been calculated. It is found that the set of parallel planes of hydrogen atoms is formed at pressure ~175 GPa as a result of structural changes in the unit cell of the crystal under pressure. There should be complete concentration of hydrogen atoms in these planes. As a result the electron properties of the system acquire a quasi-two-dimensional character. The features of in phase and antiphase oscillations of hydrogen atoms in these planes leading to two narrow high-energy peaks in the phonon density of states are investigated.

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Nikolay Degtyarenko, Evgeny Mazur. 2015-07-21. Causes of high-temperature superconductivity in the hydrogen sulfide electron-phonon system. https://arxiv.org/abs/1507.05749

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