title: Parity effect in the ground state localization of antiferromagnetic chains coupled to a ferromagnet.
abstract: We investigate the ground states of antiferromagnetic Mn nanochains on Ni(110) by spin-polarized scanning tunneling microscopy in combination with theory. While the ferrimagnetic linear trimer experimentally shows the predicted collinear classical ground state, no magnetic contrast was observed for dimers and tetramers where noncollinear structures were expected based on ab initio theory. This striking observation can be explained by zero-point energy motion for even-numbered chains derived within a classical equation of motion leading to nonclassical ground states. Thus, depending on the parity of the chain length, the system shows a classical or a quantum behavior.
authors.affiliation: Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Holzberger
authors.affiliation: Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Schuh
authors.affiliation: Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Blügel
authors.affiliation: Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany.
authors.forename: Samir
authors.initials: S
authors.lastname: Lounis
authors.affiliation: Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, 76131 Karlsruhe, Germany.
authors.forename: Wulf
authors.initials: W
authors.lastname: Wulfhekel