Relaxation et polarisation des cristaux de La2Mg3 (NO3)12, 24H2O dopé au Dy3+

Publisher Website
Google Scholar
Abstract
This paper reports details of measurements of proton relaxation time and dynamic polarization in LMN doped with Dy3+. We have measured the electronic relaxation time for the parallel and perpendicular orientations in the static magnetic field. They confirm that there are two doublets X and Y whose admixture by the static magnetic field is orientation dependant. We also measured the nuclear relaxation time for different fields and temperatures, for the two orientations. The comparison with the results of various nuclear relaxation theories shows undoubtly the importance of the (1 — P20) term. High nuclear polarization in low magnetic fields has not been achieved due to the phononbottleneck and the fact that the forbidden lines are not sufficiently separated from the electronic line. At high fields and with 126 kMHz irradiation, we obtained polarization as high as in LMN doped with Nd3+