Open AccessEnhancement of magneto-optical Kerr effect by surface plasmons in trilayer structure consisting of double-layer dielectrics and ferromagnetic metal
Author(s) -
Terunori Kaihara,
Takeaki Ando,
Hiromasa Shimizu,
Vadym Zayets,
H. Saito,
Koji Ando,
Shinji Yuasa
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.011537
Subject(s) - materials science , kerr effect , surface plasmon , optics , magneto optic kerr effect , condensed matter physics , dielectric , surface plasmon polariton , scattering , polarization (electrochemistry) , refractive index , ferromagnetism , magnetization , plasmon , optoelectronics , magnetic field , physics , chemistry , quantum mechanics , nonlinear system
Giant enhancement of the magneto-optical Kerr effect (MOKE) by surface plasmon polaritons (SPPs) is theoretically shown in a trilayer structure consisting of double-layer dielectrics and a ferromagnetic metal (Al2O3/SiO2/Fe). We calculated the resonant enhancement of the transverse MOKE (TMOKE) and polar MOKE (PMOKE) using the attenuated total reflection (ATR) configuration with the transfer matrix method using a 4 × 4 scattering matrix. At a specific film thickness of the low-index SiO2 layer, where confinement of the SPPs on the Fe surface becomes close to the cutoff condition, the incident light from the Al2O3 couples with the SPPs at the SiO2/Fe boundary most efficiently, resulting in resonant enhancement of the MOKE at an incident angle corresponding to the wave vector of the SPPs. The calculated PMOKE showed orthogonal transformation (90°-rotation) and almost full-orbed deformation (44°-ellipticity) of the polarization, and the TMOKE showed a change in reflectance of about 34 dB upon magnetization reversal.