Critical slowing down in the geometrically frustrated pyrochlore antiferromagnet Gd2Ti2O7
نویسندگان
چکیده
Longitudinal-field muon spin relaxation experiments have been carried out in the paramagnetic state of singlecrystal Gd2Ti2O7 just above the phase transition at Tm = 1.0 K. At high applied fields the exponential relaxation time T1 is proportional to field, whereas T1 saturates below a crossover field Bc that is ∼2.5 T at 1.5 K and decreases as Tm is approached. At low fields the relaxation rate increases markedly as the freezing temperature is approached, as expected for critical slowing down of the spin fluctuations, but the increase is suppressed by applied field. This behavior is consistent with the very long autocorrelation function cutoff time implied by the
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