Unconventional superconductivity without doping in infinite-layer nickelates under pressure.

Di Cataldo, Simone; Worm, Paul; Tomczak, Jan M; Si, Liang; Held, Karsten · Nat Commun · 2024

basic_science · Level V

Where this comes from

Abstract

High-temperature unconventional superconductivity quite generically emerges from doping a strongly correlated parent compound, often (close to) an antiferromagnetic insulator. The recently developed dynamical vertex approximation is a state-of-the-art technique that has quantitatively predicted the superconducting dome of nickelates. Here, we apply it to study the effect of pressure in the infinite-layer nickelate Sr<sub>x</sub>Pr<sub>1-x</sub>NiO<sub>2</sub>. We reproduce the increase of the critical temperature (T<sub>c</sub>) under pressure found in experiment up to 12 GPa. According to our results, T<sub>c</sub> can be further increased with higher pressures. Even without Sr-doping the parent compound, PrNiO<sub>2</sub>, will become a high-temperature superconductor thanks to a strongly enhanced self-doping of the Ni <math xmlns="http://www.w3.org/1998/Math/MathML"> <msub><mrow><mi>d</mi></mrow> <mrow> <msup><mrow><mi>x</mi></mrow> <mrow><mn>2</mn></mrow> </msup> <mo>-</mo> <msup><mrow><mi>y</mi></mrow> <mrow><mn>2</mn></mrow> </msup> </mrow> </msub> </math> orbital under pressure. With a maximal T<sub>c</sub> of 100 K around 100 GPa, nickelate superconductors can reach that of the best cuprates.