Spin dynamics in CeB6 studied by muon spin relaxation

The dynamics of magnetic fluctuations in the paramagnetic and antiferroquadrupolarly (AFQ) ordered phases of single crystal CeB6 was investigated by means of muon spin relaxation experiments. Applied magnetic fields up to 2.5 T were used. Since in the AFQ phase the contact hyperfine coupling that contributes to the fluctuating field amplitudes at the three d-type interstitial muon sites strongly depends on the temperature and the applied field, as shown by the corresponding Knight-shift results, this feature was taken into account in determining the magnetic fluctuation rates. The extracted correlation time tau(c) of the magnetic fluctuations depends only weakly on the applied field, its temperature dependence demonstrates an accelerated slowing down of the spin dynamics in parallel with the development of the AFQ order.