New method of controlling reproducibility in bubble garnet LPE growth

Deviations from the optimum growth temperature are a main cause of non-reproducibility of the collapse field H
o
in LPE growth o garnet bubbles materials. No solution to this problem in form of a modification to the growth process has been presented in the literature A mathematical analysis shows that the growth temperature dependence of the magnetization, (d/dT
G
) 4πM, is the most important parameter to be controlled. This can be done by employing different types of non-magnetic ions, such as Al
³⁺
or Ga
³⁺
in combination with Si
⁴⁺
or Ge
⁴⁺
. Data are given which allow the calculation of melt compositions in the Ga-CaGe system, for which H
o
of the grown film is insensitive to variations in the growth temperature. As an example a YSmLuCaFeGaGe garnet melt is given for the growth of 3/μm bubble diameter films of which H
o
varies only ± 0.5% in a 10°C interval of the growth temperature. The Curie temperature of these films is higher than 166°C.