Abstract
We report on superconductivity in Nd(1-x)Eu(x)NiO(2) using Eu as a 4f dopant of the parent NdNiO(2) 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 CaH(2) reduction process to induce superconductivity in the infinite-layer nickelates. The Nd(1-x)Eu(x)NiO(2) 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.