NMR and NQR studies of URu2Si2

We have performed Si-29 NMR and Ru-101 NQR measurements on a single crystal line URu2Si2. From the Si-29 NMR measurements, any appreciable internal fie ld at Si site was not observed in the antiferromagnetic state, indicating t hat tiny magnetic moments of U are not static but fluctuating faster than t he NMR frequency. From the Ru-101 NQR line which is much narrower than that of polycrystalline powder, the electric quadrupole interaction parameter ( va) was precisely evaluated to be 5.713 MHz at 4.2 K. (C) 2000 Elsevier Sci ence B.V. All rights reserved.