title: 29Si NMR and hidden order in URu2Si2.
abstract: Below T(N) approximately 17 K the 29Si NMR line in URu2Si2 exhibits a previously unobserved field-independent nearly isotropic contribution to the linewidth, which increases to approximately 12 G as T-->0. We argue that this feature does not arise from static freezing of the U-spin magnetization, but is due to coupling between 29Si spins and a hidden order parameter. We discuss time-reversal symmetry-breaking orbital antiferromagnetism and indirect nuclear spin-spin interactions as possible coupling mechanisms. Further NMR experiments and theoretical calculations are suggested.
authors.affiliation: Department of Physics and Astronomy, California State University, Los Angeles, California 90032, USA.
authors.forename: O O
authors.initials: OO
authors.lastname: Bernal
authors.forename: C
authors.initials: C
authors.lastname: Rodrigues
authors.forename: A
authors.initials: A
authors.lastname: Martinez
authors.forename: H G
authors.initials: HG
authors.lastname: Lukefahr
authors.forename: D E
authors.initials: DE
authors.lastname: MacLaughlin
authors.forename: A A
authors.initials: AA
authors.lastname: Menovsky
authors.forename: J A
authors.initials: JA
authors.lastname: Mydosh