Coexistence of antiferromagnetism and superconductivity in Mn/Nb(110)
Roberto Lo Conte, Maciej Bazarnik, Krisztián Palotás, Levente Rózsa, L. Szunyogh, André Kubetzka, Kirsten von Bergmann, R. Wiesendanger
Abstract
We report on the structural, magnetic, and superconducting properties of single and double atomic layers of Mn on a clean and unreconstructed Nb(110) substrate. Low-temperature scanning tunneling spectroscopy measurements reveal a proximity-induced superconducting state and in-gap Yu-Shiba-Rusinov bands in the Mn thin films, which are found to grow pseudomorphically on the Nb surface. Spin-polarized scanning tunneling microscopy measurements reveal a $c(2\ifmmode\times\else\texttimes\fi{}2)$ antiferromagnetic (AFM) order in the Mn layers, with an out-of-plane spin orientation. First-principles density functional theory calculations confirm the experimentally observed magnetic state, which is understood as the consequence of a strong intralayer and interlayer nearest-neighbor AFM exchange coupling. These results are expected to be of importance for the design of superconducting AFM spintronic systems and quantum information technologies.