Perpustakaan Digital ITB

Magnetooptical Kerr effect (MOKE) is well-known to be generated by the changes of refractive index in the presence of a magnetic field that can change the polarization state of the reflected wave. Magnetooptical effects have been applied for wide range of applications such as data recording, optical modulators, bio-sensing, and magnetic detection. MOKE can produce light polarization which is perpendicular to the polarization of incident wave. Enhancement of MOKE can be obtained by increasing the perpendicular component or reducing the parallel component of the reflected wave polarization. It has been shown in previous study of metamaterial, that the suppression of backscattering field can be achieved by superposition of some optical modes that cancel each other. In this work, we study how to enhance MOKE using backscattering suppression on the parallel component polarization of the reflected wave. We did numerical calculation by using FDTD simulation on Yttrium Iron Garnet (YIG) nanoparticle. The result shows that this set up can produce value of MOKE up to 7.5 milliradians. The enhancement of Kerr effect not only occurs at the suppression of ???????? component of backscattered wave, but ???????? component which is induced by MO activity also has contribution to increase Kerr effect. Multipole analysis shows that the suppression of ???????? component in the wavelength 492 nm and 723 nm at backscattering are obtained by different composition of optical modes. According to the result, the maximum point of field component that is induced by MO activity, is around the minimum point of non-MO field. So that, the enhancement of MOKE can always be obtained around the wavelength that the suppression of non-MO field occurs due to this unique behaviour.