Strain-stabilized superconductivity.

Ruf, J P; Paik, H; Schreiber, N J; Nair, H P; Miao, L; Kawasaki, J K; Nelson, J N; Faeth, B D et al. · Nat Commun · 2021

basic_science · Level V

Where this comes from

Abstract

Superconductivity is among the most fascinating and well-studied quantum states of matter. Despite over 100 years of research, a detailed understanding of how features of the normal-state electronic structure determine superconducting properties has remained elusive. For instance, the ability to deterministically enhance the superconducting transition temperature by design, rather than by serendipity, has been a long sought-after goal in condensed matter physics and materials science, but achieving this objective may require new tools, techniques and approaches. Here, we report the transmutation of a normal metal into a superconductor through the application of epitaxial strain. We demonstrate that synthesizing RuO<sub>2</sub> thin films on (110)-oriented TiO<sub>2</sub> substrates enhances the density of states near the Fermi level, which stabilizes superconductivity under strain, and suggests that a promising strategy to create new transition-metal superconductors is to apply judiciously chosen anisotropic strains that redistribute carriers within the low-energy manifold of d orbitals.