Dynamical properties of magnetically frustrated pyrochlore system Tb2Ti2O7

sNeutron scattering studies have been carried out on a single crystal of a pyrochlore compound Tb2Ti2O7 with geometrically frustrated magnetic moments . The temperature (T) dependence of the dynamical magnetic properties and d ispersion curves of the magnetic excitation have been studied in detail, wh ere we have identified the pattern of the short-range magnetic correlation and determined the T-dependence of the correlation length. Neutron measurem ents in the magnetic fields (H) up to 4.5 T applied along the [1 (1) over b ar1] direction have also been carried out. The magnetic scattering intensit y increases at several nuclear Bragg points with increasing H. Although the magnetic structure has not been determined, the results seem to indicate t hat an antiferromagnetic long-range order is induced by applying the relati vely small magnetic held. (C) 2000 Elsevier Science Ltd. All rights reserve d.