One-dimensional spin fluctuations in a transition metal oxide

J. F. DiTusa, Nokia Bell Labs
S. W. Cheong, Nokia Bell Labs
C. Broholm, Johns Hopkins University
G. Aeppli, Nokia Bell Labs
L. W. Rupp, Nokia Bell Labs
B. Batlogg, Nokia Bell Labs


We use inelastic neutron scattering from polycrystalline Y2BaNiO5 and Y2BaNi0.96Zn0.04O5 specimens to demonstrate that the spin fluctuations in this compound are one-dimensional. In addition they are gapped, in accord with the S=1 nature of the Ni2+ and the Haldane conjecture. The gap remains well defined and may even grow slightly in the Zn-diluted compound. © 1994.