Exploration of the theory for spin-cavity coupling in inhomogeneously
broadened spin ensembles shows that all three components of magnetizat
ion can be refocused. The conventional spin echo generated by two comp
onents of magnetization is a special case of this three component refo
cusing in the limit of negligible radiation damping. We demonstrate th
is effect by an analytical theorem, numerical simulation, and experime
nt. (C) 1997 American Institute of Physics.