Magnetic nanocomposite films with photo-patterned 1D grating on top enable giant magneto-optical intensity effects

The enhancement of magneto-optical (MO) effects in planar devices is commonly obtained through the combination of a plasmonic resonance and a MO material, or through the microstructuration of such materials. However, the devices often suffer from weak optical signal, or require fastidious lithography processes. We present a much simpler device made of a photoresist 1D grating processed on a MO composite planar waveguide. This latter is formed by magnetic nanoparticles embedded in a silica matrix. Such all-dielectric device produces much higher Q-factor resonances, which finally result in giant MO intensity effects. Their magnitude combined with the ability of the device to be processed on large scale and various substrates, are very promising for a wide range of sensing applications.