title: Quantum engineering of spin and anisotropy in magnetic molecular junctions.
abstract: Single molecule magnets and single spin centres can be individually addressed when coupled to contacts forming an electrical junction. To control and engineer the magnetism of quantum devices, it is necessary to quantify how the structural and chemical environment of the junction affects the spin centre. Metrics such as coordination number or symmetry provide a simple method to quantify the local environment, but neglect the many-body interactions of an impurity spin coupled to contacts. Here, we utilize a highly corrugated hexagonal boron nitride monolayer to mediate the coupling between a cobalt spin in CoHx (x=1,2) complexes and the metal contact. While hydrogen controls the total effective spin, the corrugation smoothly tunes the Kondo exchange interaction between the spin and the underlying metal. Using scanning tunnelling microscopy and spectroscopy together with numerical simulations, we quantitatively demonstrate how the Kondo exchange interaction mimics chemical tailoring and changes the magnetic anisotropy.
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Jacobson
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Herden
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Muenks
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: Gennadii
authors.initials: G
authors.lastname: Laskin
authors.affiliation: Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle(Saale), Germany.
authors.forename: Oleg
authors.identifier: http://orcid.org/0000-0002-0443-5365
authors.initials: O
authors.lastname: Brovko
authors.affiliation: Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle(Saale), Germany.
authors.forename: Valeri
authors.initials: V
authors.lastname: Stepanyuk
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Ternes
authors.affiliation: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.|Institute de Physique de la Matière Condensée, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kern