Hole superconductivity in infinite-layer nickelates

TL;DR

This paper suggests that superconductivity in infinite-layer nickelates arises from the same hole pairing mechanism as in cuprates, driven by correlated hopping, and predicts increased critical temperatures under strain.

Contribution

It extends the hole superconductivity theory to nickelates, proposing a common pairing mechanism with cuprates and predicting strain-induced Tc enhancement.

Findings

Superconductivity in Nd$_{0.8}$Sr$_{0.2}$NiO$_2$ is due to hole pairing in oxygen pπ orbitals.

The pairing mechanism involves a correlated hopping term that lowers kinetic energy.

Compressive strain is predicted to significantly increase the critical temperature.

Abstract

We propose that the superconductivity recently observed in Nd$_{0.8}$Sr$_{0.2}$NiO$_2$ with critical temperature in the range $9$ K to $15$ K results from the same charge carriers and the same mechanism that we have proposed give rise to superconductivity in both hole-doped and electron-doped cuprates: pairing of hole carriers in oxygen $p\pi$ orbitals, driven by a correlated hopping term in the effective Hamiltonian that lowers the kinetic energy, as described by the theory of hole superconductivity. We predict a large increase in $T_c$ with compressive epitaxial strain.