29Si NMR and hidden order in URu2Si2.
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.
Bernal
O O
OO
Department of Physics and Astronomy, California State University, Los Angeles, California 90032, USA.
Rodrigues
C
C
Martinez
A
A
Lukefahr
H G
HG
MacLaughlin
D E
DE
Menovsky
A A
AA
Mydosh
J A
JA