Extensive Hydrogen Incorporation is not Necessary for Superconductivity in Topotactically Reduced Nickelates

Published

August 27, 2024

Author(s)

Purnima Balakrishnan, Dan Segedin, Lin Chow, P. Quarterman, Shin Muramoto, Mythili Surendran, Ranjan Patel, Harrison LaBollita, Grace Pan, Qi Song, Yang Zhang, Ismail El Baggari, Koushik Jagadish, Yu-Tsun Shao, Berit Goodge, Lena Kourkoutis, Srimanta Middey, Antia Botana, Jayakanth Ravichandran, A. Ariando, Julia A. Mundy, Alexander Grutter

Abstract

A key open question in the study of layered superconducting nickelate films is the role that hydrogen incorporation into the lattice plays in the appearance of the superconducting state. Due to the challenges of stabilizing highly crystalline square planar nickelate films, films are prepared by the deposition of a more stable parent compound which is then transformed into the target phase via a topotactic reaction with a strongly reducing agent such as CaH2. Recent studies, both experimental and theoretical, have introduced the possibility that the incorporation of hydrogen from the reducing agent into the nickelate lattice may be critical for the superconductivity. In this work, we use secondary ion mass spectrometry to examine superconducting La1−xXxNiO2 / SrTiO3 (X = Ca and Sr) and Nd6Ni5O12/ NdGaO3 films, along with non-superconducting NdNiO2 / SrTiO3 and (Nd,Sr)NiO2 / SrTiO3. We find no evidence for extensive hydrogen incorporation across a broad range of samples, including both superconducting and non-superconducting films. Theoretical calculations indicate that hydrogen incorporation is broadly energetically unfavorable in these systems, supporting our conclusion that extensive hydrogen incorporation is not generally required to achieve a superconducting state in layered square-planar nickelates.

Citation

Nature Communications

Volume

15

Pub Type

Journals

Download Paper

https://doi.org/10.1038/s41467-024-51479-3

Local Download

Keywords

Superconductivity, Thin film, hydrogen, materials, nickelate

Citation

Balakrishnan, P. , Segedin, D. , Chow, L. , Quarterman, P. , Muramoto, S. , Surendran, M. , Patel, R. , LaBollita, H. , Pan, G. , Song, Q. , Zhang, Y. , El Baggari, I. , Jagadish, K. , Shao, Y. , Goodge, B. , Kourkoutis, L. , Middey, S. , Botana, A. , Ravichandran, J. , Ariando, A. , Mundy, J. and Grutter, A. (2024), Extensive Hydrogen Incorporation is not Necessary for Superconductivity in Topotactically Reduced Nickelates, Nature Communications, [online], https://doi.org/10.1038/s41467-024-51479-3, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=957663 (Accessed November 21, 2024)