MAGNETIC PHASE-DIAGRAM OF EPITAXIAL DYSPROSIUM

We have determined the magnetic phase diagram of Dy as a function of e xpitaxial strain epsilon, applied field H, and temperature T. YxLu1-x alloys were employed as templates to clamp the films at selected strai ns. The separate roles of epitaxial clamping and strain are identified for the first time. There is a clearly defined transition as the stra in is changed at low temperature from the clamped helical phase to the ferromagnetic phase. The transition is modeled by a linear coupling t reatment of the magnetoelastic strains.