1. The quantum and anharmonic effects on the vibrational and superconducting properties of H3Se in Im-3m phase under high pressure
- Author
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Ma, Yao, Li, Mingqi, Shi, Wenjia, Wang, Vei, Hou, Pugeng, and Pang, Mi
- Subjects
Condensed Matter - Superconductivity - Abstract
Hydrogen-based compounds have attracted significant attention in recent years due to the discovery of conventional superconductivity with high critical temperature under high pressure, rekindling hopes for searching room temperature superconductor. In this work, we investigated systematically the vibrational and superconducting properties of H3Se in Im-3m phase under pressures ranging from 75 to 200 GPa. Our approach combines the stochastic self-consistent harmonic approximation with first-principles calculations to address effects from the quantum and anharmonic vibrations of ions. It turns out that these effects significantly modify the crystal structure, increasing the inner pressure by about 8 GPa compared to situations where they are ignored. The phonon spectra suggest that with these effects included, the crystal can be stabilized at pressures as low as about 55 GPa, much lower than the previously predicted value of over 100 GPa. Our calculations also highlight the critical role of quantum and anharmonic effects on electron-phonon coupling properties. Neglecting these factors could result in a substantial overestimation of the superconducting critical temperature, by approximately 25 K at 125 GPa, for example., Comment: 7 pages, 3 figures, submitted to Chinese Physics Letters
- Published
- 2024