Anisotropy and magnetostriction of gallium-substituted yttrium iron garnet

The anisotropy and magnetostriction constants of gallium-substituted yttrium iron garnet single crystals of composition Y3Fe5−tGatO12 with 0≤t≤1.5 have been investigated by means of ferrimagnetic resonance in the temperature range 4.2≤T≤500 K. From the concentration dependence at T =4.2 K the single-ion contribution of the tetrahedral and octahedral anisotropy was found to be Kd = −0.0019 cm−1 and Ka = −0.012 cm−1, respectively. In the range t1 of linear concentration dependence of the magnetostriction constants at T=4.2 K, a variation Δλ100/t = −1.3×10−6 and Δλ111/t = +3.0×10−6 was found.