Cu doping effect on FePt grains prepared by rapid thermal annealing on SiO_2 substrate and wall structure in TbFeCo/FePt CGC-like film

摘要

We report that Cu substitution is effective in raising the degree of (001) crystal orientation of FePt grains prepared by rapid thermal annealing on SiO_2. We fabricated coupled granular and continuous (CGC) like films such as TbFeCo on FePt grains. The wall coercivity was about twice that of the TbFeCo single layer film. From three-dimensional micromagnetic simulations with Landau-Lifshitz-Gilbert (LLG) equation, it was confirmed that wall coercivity was enhanced and domain shapes made smooth in CGC film. When the thickness of the TbFeCo layer was thin, wall width was thinner than the theoretical value.