Crystals structures; Hybrid structure; Normal metals; Proximity effects; Stackings; Superconducting order parameters; Thin layers; Physics and Astronomy (miscellaneous)
Abstract :
[en] We present an unexpectedly strong influence of the proximity effect between the bulk Ru(0001) superconductor and atomically thin layers of Co on the crystal structure of the latter. The Co monolayer grows in two different modifications, such as hcp stacking and a reconstructed ϵ-like phase. While hcp islands show a weak proximity effect on Co and a little suppression of superconductivity in the substrate next to it, the more complex ϵ-like stacking becomes almost fully superconducting. We explain the weak proximity effect between Ru and hcp Co and the rather abrupt jump of the superconducting order parameter by a low transparency of the interface. In contrast, the strong proximity effect without a jump of the order parameter in the ϵ-like phase indicates a highly transparent interface. This work highlights that the proximity effect between a superconductor and a normal metal strongly depends on the crystal structure of the interface, which allows to engineer the proximity effect in hybrid structures.
Disciplines :
Physics
Author, co-author :
Mougel, Loic; Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
Buhl, Patrick M.; Institute of Physics, Johannes Gutenberg University Mainz, Mainz, Germany
Li, Qili ; Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
Müller, Anika; Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
Yang, Hung-Hsiang ; Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
Verstraete, Matthieu ; Université de Liège - ULiège > Département de physique > Physique des matériaux et nanostructures
Simon, Pascal ; Laboratoire de Physique des Solides, UMR 8502, CNRS, Université Paris-Sud, Université Paris-Saclay, Orsay, France
Dupé, Bertrand ; Université de Liège - ULiège > Département de physique > Physique des matériaux et nanostructures ; Fonds de la Recherche Scientifique (FNRS), Bruxelles, Belgium
Wulfhekel, Wulf ; Physikalisches Institut, Karlsruhe Institute of Technology, Karlsruhe, Germany
Language :
English
Title :
Strong effect of crystal structure on the proximity effect between a superconductor and monolayer of cobalt
DFG - Deutsche Forschungsgemeinschaft AvH - Alexander von Humboldt-Stiftung
Funding text :
W. Wulfhekel acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG) under Grant Nos. WU 349/15-1 and WU 349/16-1. H. S. Yang acknowledges funding by the Alexander-von-Humboldt Foundation. B. Dupé and P. Buhl acknowledge funding by the DFG under Grant No. DU 1489/3-1.
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