Magnetic excitations and soft-mode transition in Pr2BaNiO5
Brookhaven National Laboratory - Upton, NY 11973-5000, USA
2 University of Delaware - Newark, DE 19716, USA
Accepted: 17 June 1996
The quasi–1-dimensional (1D) antiferromagnet Pr2BaNiO5 was studied by single-crystal inelastic neutron scattering. Magnetic gap excitations of 1D nature in the S=1 Ni chains were observed above and below the Néel temperature K. Two temperature-dependent magnetic-exciton bands were found and associated with a crystal field transition in Pr. One of these modes was found to undergo a complete softening at the antiferromagnetic wave vector as from above, driving the magnetic ordering.
PACS: 75.30.Ds – Spin waves / 75.40.Gb – Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.) / 75.10.Jm – Quantized spin models
© EDP Sciences, 1996