Robust superconductivity in the high-symmetry La-Y solid solution alloy under high pressure

Abstract

Rare-earth (RE) elements exhibit diverse crystal structures and unique physicochemical properties under pressure, such as complex magnetic behavior and intriguing superconducting properties. Among them, lanthanum (La) exhibits enhanced superconductivity under compression. However, pressure-induced structural distortion and symmetry reduction modify its electronic properties, significantly reducing its superconducting temperature (Tc) from its maximum value of 13.1 K at pressures exceeding 78 GPa. To optimize its Tc, we employ an alloying strategy in this study, partially substituting La with yttrium (Y) to modulate its structural symmetry under high pressure, a key factor for Tc. X-ray diffraction measurements reveal a phase transition in the La-Y alloy from an ambient hexagonal structure to a face-centered cubic phase at ∼11 GPa, maintaining high symmetry up to at least 170 GPa. Electrical transport measurements confirm that this cubic phase exhibits robust superconductivity, reaching a maximum Tc of 13.6 K at 65 GPa. These findings provide a platform for modulating structural symmetry and physical properties through alloying, highlighting the potential for discovering superior superconductivity in RE materials under extreme conditions.

Source-reported materials — not catalogue approval

Similar papers