Growth and magnetic properties of bismuth garnet flims for magneto-optic devices

A series of about 200 Bi
x
Tm
3-x
Fe
y
Ga
5-y
O
12
films were grown by the liquid phase epitaxy method onto 50mm GGG substrates. Special attention was paid to measurement of films with H
co11
≤ 35 gauss and anisotropy fields (H*
k
) from 1000-5000 gauss. Atomic absorption analysis showed that the range of Bi
³⁺
in our materials was 0.63
\leq X \leq0.88
while Fe was found to he between 3.69 and 3.75 formula units. Curie temperatures for these films were between 389°K (X
Bi
= 0.63) and 408°K (X
Bi
= 0.88). Faraday rotation varied from 0.51°/μ(X
Bi
= 0.63) to 0.86°/μ (X
Bi
= 0.88). It was found that H*
k
and H
co11
could be controlled in a manner which allowed films with tailored magnetic properties and high Faraday rotation to be produced.