Magnetic susceptibility as a macroscopic entanglement witness

Author(s): Marcin Wiesniak, Vlatko Vedral, Caslav Brukner
Abstract: We show that magnetic susceptibility can reveal spin entanglement between individual constituents of a solid, while magnetization describes their local properties. We then show that magnetization and its variance (equivalent to magnetic susceptibility for a wide class of systems) satisfy complementary relation in the quantum-mechanical sense. It describes sharing of (quantum) information in the solid between spin entanglement and local properties of its individual constituents. Magnetic susceptibility is shown to be a macroscopic (thermodynamical) spin entanglement witness that can be applied without complete knowledge of the specific model (Hamiltonian) of the solid. Œ IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
Organisation(s)
External organisation(s): Erwin Schrödinger Institut
Journal: New Journal of Physics
Volume: 7
No. of pages: 8
ISSN: 1367-2630
DOI: https://doi.org/10.1088/1367-2630/7/1/258
Publication date: 2005
Peer reviewed: Yes
Austrian Fields of Science 2012: 103026 Quantum optics
Portal url: https://ucris.univie.ac.at/portal/en/publications/magnetic-susceptibility-as-a-macroscopic-entanglement-witness(e8b07e0c-c4e0-4147-880c-cec16829d492).html