title: Magnetic dilution in the geometrically frustrated SrCr(9p)Ga(12-9p)O19 and the role of local dynamics: A muon spin relaxation study
abstract: We investigate the spin dynamics of SrCr(9p)Ga(12-9p)O19 for p below and above the percolation threshold p(c) using muon spin relaxation. Our major findings are as follows: (i) At T-->0 the relaxation rate is T independent and approximately p(3), (ii) the slowing down of spin fluctuation is activated with an energy U, which is also a linear function of p(3) and lim U as p-->0 = 8 K; this energy scale could stem only from a single ion anisotropy, and (iii) the p dependence of the dynamical properties is identical below and above p(c), indicating that they are controlled by local excitation.
authors.affiliation: Department of Physics, Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.initials: A
authors.lastname: Keren
authors.initials: YJ
authors.lastname: Uemura
authors.initials: G
authors.lastname: Luke
authors.initials: P
authors.lastname: Mendels
authors.initials: M
authors.lastname: Mekata
authors.initials: T
authors.lastname: Asano