Observation of fractional harmonics in the NMR signal from superfluid He-3-B

Unusual spin-precession states of He-3-B in which the magnetization is half the equilibrium value are investigated by continuous-wave NMR methods. Sig nals at frequencies equal to 1/2 and 3/2 of the magnetization precession fr equency are observed in two such states. Such signals exist because the ord er parameter of superfluid He-3 in these states precesses with frequency eq ual to half the magnetization precession frequency. (C) 1999 American Insti tute of Physics.