Crystals Miguel Levy, Michigan Technological University, DMR 0709669 This project focuses on the development of new magnetic materials with strong nonlinear magnetic susceptibility. A total of 43 bismuth-substituted iron garnet (Bi,Y) 3-x (Fe,Ga) 5-y O 12 (Bi:YIG) films were sputter- deposited and characterized for crystalline structure, composition and nonlinear response. It was found that in unannealed Bi:YIG films lattice mismatch strain drives the second harmonic (SH) signal, while in annealed films micro- strain controls the SH signal in the absence of an external magnetic field. Hyper-Rayleigh scattering measurements showed that oriented crystallites produce strong non-diffusive SH generation. A sought-for magnetization dependence of the (a) Strong SH signal dependence on lattice mismatch strain for un-annealed samples. (b) SH signal shows dependence on micro- strain in annealed samples. (c) HRS indicatrix of a film shows sharp non- diffusive SH contribution from oriented crystallites, (d) Magnetic contrast study evincing that the SH signal depends strongly on magnetic field direction (a) 0 100 200 300 400 500 1 2 3 1 3 S a m p le , 6 0m W PP S ig n a l, a .u. T im e , se c 100 200 300 400 500 0 1 2 3 S.H. Signal (a.u.) Time (sec.) (d) 60 mW PP geometry Dubrovina, Kumar, Levy, Maydykovskiy, Aktsipetrov, Moscow Intern. Symp. on Magn. (MISM 2011) (b) (c)