Superconducting Nd1- xEu x NiO2 thin films using in situ synthesis

Wenzheng Wei; Dung Vu; Zhan Zhang; Frederick J Walker; Charles H Ahn

doi:10.1126/sciadv.adh3327

Superconducting Nd_{1- x}Eu _x NiO₂ thin films using in situ synthesis

Sci Adv. 2023 Jul 7;9(27):eadh3327. doi: 10.1126/sciadv.adh3327. Epub 2023 Jul 5.

Authors

Wenzheng Wei¹, Dung Vu¹, Zhan Zhang², Frederick J Walker¹, Charles H Ahn^{1

3

4}

Affiliations

¹ Department of Applied Physics, Yale University, New Haven, CT 06520, USA.
² Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA.
³ Department of Physics, Yale University, New Haven, CT 06520, USA.
⁴ Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06520, USA.

Abstract

We report on superconductivity in Nd_1-xEu_xNiO₂ using Eu as a 4f dopant of the parent NdNiO₂ infinite-layer compound. We use an all-in situ molecular beam epitaxy reduction process to achieve the superconducting phase, providing an alternate method to the ex situ CaH₂ reduction process to induce superconductivity in the infinite-layer nickelates. The Nd_1-xEu_xNiO₂ samples exhibit a step-terrace structure on their surfaces, have a T_c onset of 21 K at x = 0.25, and have a large upper critical field that may be related to Eu 4f doping.