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arXiv · 2311.08070

First Principles Prediction Unveils High-T$_c$ Superconductivity in YSc$_2$H$_{24}$ Cage Structures

Abstract

The quest for room-temperature superconductivity has been a long-standing aspiration in the field of materials science, driving extensive research efforts. In this work, we present a novel hydride, YSc$_2$H$_{24}$, which is stable at high pressure, identified through crystal structure prediction methods. The discovered material is crystalline in a hexagonal unit cell with space group $P6/mmm$ and has a fastinating structure consisting of two distinct cages: Sc@H$_{24}$ and Y@H$_{30}$. By conducting an extensive numerical investigation of lattice dynamics, electron-phonon coupling, and solving the isotropic Eliashberg equation, we have revealed a significant value of $\lambda$ = 3.27 as the underlying factor responsible for the remarkably high critical temperature (T$_c$) of 302-330 K in YSc$_2$H$_{24}$ at a pressure of 310 GPa. As pressure increases, the T$_c$ remains above the ambient temperature. Our work has the potential to enhance the existing understanding of high-temperature superconductors, with implications for practical applications. The unique network of these cage-like structures holds great promise for advancing our understanding of high-temperature superconductors, potentially leading to innovative applications.

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Truong-Tho Pham, Viet-Ha Chu, Duc-Long Nguyen. 2023-11-14. First Principles Prediction Unveils High-T$_c$ Superconductivity in YSc$_2$H$_{24}$ Cage Structures. https://doi.org/10.1039/d4tc03145h

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