title: Quantum spin correlations in an organometallic alternating-sign chain.
abstract: High resolution neutron scattering is used to study excitations in the organometallic magnet (CH3)2NH2CuCl3 (DMACuCl3). Combined with bulk magnetization and susceptibility studies, the new results imply that DMACuCl3 is a realization of the S=1/2 alternating antiferromagnetic-ferromagnetic (AFM-FM) chain. Coupled-cluster calculations indicate that the AFM and FM interactions have nearly the same strength, while analysis of scattering intensities shows evidence for interdimer spin correlations. Results are discussed in the context of recent ideas concerning quantum entanglement.
authors.affiliation: Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Stone
authors.forename: W
authors.initials: W
authors.lastname: Tian
authors.forename: M D
authors.initials: MD
authors.lastname: Lumsden
authors.forename: G E
authors.initials: GE
authors.lastname: Granroth
authors.forename: D
authors.initials: D
authors.lastname: Mandrus
authors.forename: J-H
authors.initials: JH
authors.lastname: Chung
authors.forename: N
authors.initials: N
authors.lastname: Harrison
authors.forename: S E
authors.initials: SE
authors.lastname: Nagler