|Title||$^8$Li$^+$ $\beta$-NMR in the Cubic Insulator MgO|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||MacFarlane, WA, Parolin, TJ, Cortie, DL, Chow, KH, Hossain, MD, Kiefl, RF, Levy, CDP, McFadden, RML, Morris, GD, Pearson, MR, Saadaoui, H, Salman, Z, Song, Q, Wang, D|
|Journal||J. Phys.: Conf. Ser.|
We present extensive high magnetic field β -NMR measurements of 8 Li + implanted in single crystals of MgO. The narrow resonance, consistent with a cubic 8 Li + site, likely the tetrahedral interstitital, is used routinely as a reference for shift measurements. We show the intrinsic linewidth is on the order of 200 Hz, allowing a frequency determination to an accuracy of a few Hz. We find no implantation energy dependence of the resonance within a few ppm, but there is evidence of slow spin dynamics in hole-burning measurements. The spin lattice relaxation is slow. The temperature dependence reveals interesting changes at low temperature whose origin remains uncertain.