title: Quantum Einstein-de Haas effect.
abstract: The classical Einstein-de Haas experiment demonstrates that a change of magnetization in a macroscopic magnetic object results in a mechanical rotation of this magnet. This experiment can therefore be considered as a macroscopic manifestation of the conservation of total angular momentum and energy of electronic spins. Since the conservation of angular momentum is a consequence of a system's rotational invariance, it is valid for an ensemble of spins in a macroscopic ferromaget as well as for single spins. Here we propose an experimental realization of an Einstein-de Haas experiment at the single-spin level based on a single-molecule magnet coupled to a nanomechanical resonator. We demonstrate that the spin associated with the single-molecule magnet is then subject to conservation of total angular momentum and energy, which results in a total suppression of the molecule's quantum tunnelling of magnetization.
authors.affiliation: Institut Néel, CNRS &Université Joseph Fourier, BP 166, 25 Avenue des Martyrs, 38042 Grenoble Cedex 9, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Ganzhorn
authors.affiliation: Institut of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Klyatskaya
authors.affiliation: Institut of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany.|Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), CNRS-Université de Strasbourg, 67034 Strasbourg, France.
authors.forename: Mario
authors.identifier: http://orcid.org/0000-0002-7718-7016
authors.initials: M
authors.lastname: Ruben
authors.affiliation: Institut Néel, CNRS &Université Joseph Fourier, BP 166, 25 Avenue des Martyrs, 38042 Grenoble Cedex 9, France.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wernsdorfer