A MODEL FOR THE OCCURRENCE OF LOCK-INS IN HOLMIUM IN C-AXIS MAGNETIC-FIELDS

We introduce a novel interpretation of the sequence of commensurate lo ck-ins of the spiral wave vector, tau, observed in the helimagnetic ph ase of holmium in the presence of c-axis magnetic fields. This is the first successful model for the prediction of these lock-ins. We show t hat a model that combines a spin-slip model with an assumption concern ing the spin structure along the c-axis in finite size ''domains'', yi elds excellent predictions when the energetics of this system with an applied c-axis magnetic field are considered.