ISIS Neutron and Muon Source Data Journal

Universality of the Role of Hydrogen in Superconductivity in Nickelates

Abstract: An entire family of superconducting materials of nickel oxides has recently emerged, but materials synthesis requires a two-step process, of depositing oxygen-rich films and then topochemically reducing them in the presence of hydrogen. The superconducting state is challenging to achieve, in part due to the difficulty in controlling hydrogen incorporation into the films during the reduction process. Though hydrogen has been theorized to destroy superconductivity, there have been recent yet controversial claims that hydrogen plays a critical role in and is in fact necessary to achieve superconductivity in infinite-layer Nd0.8Sr0.2NiO2 films. We have used a multimodal approach including neutron reflectometry to study hydrogen incorporation across a variety of nickelate films and have found that hydrogen content is extremely sensitive to initial film quality and the presence of microstructural defects, which can be controlled by a number of factors. However, due to well-known challenges of sample yield, we have only measured samples which do not superconduct. We propose to complete this work by measuring neutron reflectometry of superconducting films of three different compounds of the nickelate family, to understand whether the presence of hydrogen is universally necessary for supporting the superconducting state in nickelate films, or simply a proxy for microstructural defects and sample variation.

Principal Investigator: Dr Purnima Parvathy Balakrishnan
Experimenter: Professor Ariando Ariando
Experimenter: Mr LIN ER CHOW
Experimenter: Dr Alexander Grutter
Experimenter: Dr Christy Kinane
Local Contact: Dr Andrew Caruana
Experimenter: Mr Dan Ferenc Segedin

DOI: 10.5286/ISIS.E.RB2320137

ISIS Experiment Number: RB2320137

Publisher: STFC ISIS Neutron and Muon Source

Data format: RAW/Nexus
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Data Citation

The recommended format for citing this dataset in a research publication is as:
[author], [date], [title], [publisher], [doi]

For Example:
Dr Purnima Parvathy Balakrishnan et al; (2024): Universality of the Role of Hydrogen in Superconductivity in Nickelates, STFC ISIS Neutron and Muon Source, https://doi.org/10.5286/ISIS.E.RB2320137

Data is released under the CC-BY-4.0 license.