Bi-Substituted LPE Garnet Films with FMR Linewidth as Small as YIG

Abstract
Highly Bi-substituted LPE garnet films, Bi 0.85 Lu 2.15 Fe 5 O 12 and Bi 1.4 Y 1.6 Fe 5 O 12 , with FMR linewidths as small as that of YIG, have been grown using only Bi 2 O 3 as a flux. Substitution of Al for Fe causes a sharp increase in ΔH. The minimum values of ΔH obtained were 1.5 Oe for Bi 0.85 Lu 2.15 Fe 5 O 12 films and 0.73 Oe for Bi 1.4 Y 1.6 Fe 5 O 12 films, which are the smallest values reported to date for such heavily Bi-substituted garnet films. This may be ascribed to the fact that no Pb was included in the films. It was experimentally verified that MSSW propagation is possible for Bi 0.85 Lu 2.15 Fe 5 O 12 films. These films are very promising for MSW-based optical waveguide devices, since they have a specific Faraday rotation ten times larger than that of YIG, as well as a very small optical absorption coefficient at a wavelength of 1.3 /spl um/m.