New preprint announcement
Stability and Superconductivity of Ternary Polyhydrides
We are pleased to announce the submission of our latest preprint to arXiv, titled Stability and Superconductivity of Ternary Polyhydrides.
In this work, we review five years of experimental and theoretical efforts (2020-2025) aimed at enhancing superconducting critical temperatures in hydrogen-rich compounds through alloying. The guiding question has been whether adding a third element to binary superhydrides can push Tc beyond current records.
Our analysis reveals an interesting pattern: within experimental uncertainty, disordered ternary superhydrides do not exceed the maximum Tc of their binary parent compounds, despite numerous theoretical predictions to the contrary. This finding helps clarify the role of alloying in superhydride research.
However, alloying offers significant practical advantages. It stabilizes high-symmetry phases at substantially lower pressures—enabling Tc = 200 K near 110-120 GPa instead of much higher pressures—and improves properties like vortex pinning and upper critical fields. We also observe behavior reminiscent of Anderson’s theorem: magnetic dopants suppress Tc, while nonmagnetic additives leave it essentially unchanged.
Looking ahead, we propose that fully ordered ternary hydrides, synthesized through controlled hydrogenation of intermetallic precursors, represent a promising direction for achieving the benefits of alloying while potentially accessing new superconducting regimes.
This work provides clarity on what has been achieved in ternary superhydrides and offers guidance for future experimental efforts. We look forward to feedback from the community!
Check out the preprint arXiv:2509.22877.
