title: Dynamic properties of a diluted pyrochlore cooperative paramagnet (Tb(p)Y(1-p))2Ti2O7.
abstract: Investigations of the spin dynamics of the geometrically frustrated pyrochlore (Tb(p)Y(1-p))2Ti2O7, using muon spin relaxation and neutron spin echo, as a function of magnetic coverage p, have been carried out. Our major finding is that paramagnetic fluctuations prevail as T-->0 for all values of p, and that they are sensitive to dilution, indicating a cooperative spin motion. However, the percolation threshold pc is not a critical point for the fluctuations. We also find that the low temperature spectral density has a 1/f behavior, and that dilution slows down the spin fluctuations.
authors.affiliation: Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Keren
authors.forename: J S
authors.initials: JS
authors.lastname: Gardner
authors.forename: G
authors.initials: G
authors.lastname: Ehlers
authors.forename: A
authors.initials: A
authors.lastname: Fukaya
authors.forename: E
authors.initials: E
authors.lastname: Segal
authors.forename: Y J
authors.initials: YJ
authors.lastname: Uemura