Stability and superconductivity of K-Y-H hydrides under high pressure

TL;DR

This study investigates high-pressure ternary hydrides KYHn, revealing KYH8's stability and high superconducting transition temperatures up to 142.3K, suggesting potential new high-Tc superconductors.

Contribution

It introduces the stability and superconductivity of KYH8 under high pressure, expanding the search for high-Tc hydride superconductors.

Findings

KYH8 is thermodynamically stable between 50-300 GPa.

Tc of KYH8 reaches up to 142.3K at 300 GPa.

KYH8 shows promising superconducting properties under high pressure.

Abstract

It has been a hot issue to search for hydrides at high pressure with high superconducting transition temperature (Tc). In this work, ternary hydrogen-rich compounds KYHn (n = 1-16) were studied and calculated using the density function theory (DFT) method and he results showed that the KYH8 demonstrates good stability and superconductivity. And keep thermodynamically stable in the pressure range of 50-300 GPa. The research found that the Tc of KYH8-C2/m was predicted to be 111.3K, 122.0K, and 142.3K at 200, 250 and 300 GPa, respectively. Our current study provides a possibility for searching new high-Tc superconductors in ternary hydrides.