Liquid crystals in the homogeneous nematic phase possess a centrosymmetric structure, in which second harmonic generation is not possible. The application an external electric field breaks the centrosymmetry through an effect called electric poling, as well as through the flexoelectric effect, caused by reorientation of the director feld. A liquid crystal with ferromagnetic properties can be created by suspending magnetic nanoplatelets in a conventional nematic liquid crystal. In such a material reorientation can be induced not only by applying an external electric field, but also by applying an external magnetic field, which allows the study of the flexoelectric contribution to second harmonic generation without the presence of the contribution from the electric field-induced second harmonic generation. This thesis reports the First experimental measurement and analysis of second harmonic generation in a ferromagnetic liquid crystal. The addition of magnetic nanoplatelets has no significant effect on optical properties of the material other than increased absorption. When using an applied electric field, the second harmonic signal is significant in three out of six investigated polarization combinations, while by the use of a magnetic field a significant signal is observed only in one polarization combination. The conversion efficiency in the case of reorientation with a magnetic field is about five times smaller than the conversion efficiency when using an electric field.
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