Thin-film aspects of superconducting nickelates

TL;DR

This paper reviews the unique thin-film properties of superconducting nickelates, emphasizing their surface and interface effects that influence their superconductivity, which is predominantly observed in thin films unlike cuprates.

Contribution

It provides a comprehensive overview of the thin-film aspects and surface/interface effects in superconducting nickelates, highlighting differences from cuprate superconductors.

Findings

Superconductivity in nickelates is mainly observed in thin films.

Surface and interface effects are crucial in nickelate superconductivity.

Distinct behaviors between bulk and thin-film nickelates are discussed.

Abstract

The discovery of superconductivity in infinite-layer nickelates has attracted much attention due to their association to the high-$T_c$ cuprates. Cuprate superconductivity was first demonstrated in bulk samples and subsequently in thin films. In the nickelates, however, the situation has been reversed: although surging as a bulk phenomenon, nickelate superconductivity has only been reported in thin films so far. At the same time, the specifics of infinite-layer nickelates yield distinct interface and surface effects that determine their bulk vs thin-film behavior. In this paper, we provide an overview on these important aspects.