Nuclear polarization of rare-earth ions in insulating Van Vleck paramagnets
Volodin A. G., Egorov A. V., Tagirov M. S., Teplov M. A., Feller G., Schwabe H., Staudte M.
A study has been made of the spin-lattice relaxation of 14,Pr nuclei in Pr2(S04)3-8H20 and 169Tm nuclei in TmES in strong magnetic fields (up to 60 kOe) at ultralow temperatures (70-100 mK). A direct (T~l ~H4) relaxation of 14 *Pr nuclei has been detected. The relaxation rate Τ ~1 of the 169Tm nuclei does not depend on the strength of the magnetic field or the temperature.