Optical and magnetooptical properties of Co-doped YIG films

Conclusions Analysis of cobalt contributions to the Faraday rotation spectra in the series of (YCa)₃(FeCoGe)₅O₁₂ garnet films enabled us to distinguish between single contributions of Co²⁺ and Co³ ions in tetrahedral sites. It appeared that even the high counterdopes of calcium do not suppress the occurrence of tetrahedral Co²⁺ ions, although their concentration is greatly reduced in comparison with the original samples not containing any Ca. Noteworthy is also a rather high content of tetrahedral Co³⁺ in the samples not containing calcium even in cases when Ge content exceeds that of Co ions.