Near-infrared switch effect of polarization modulation induced by guided-mode resonance in dielectric grating

Abstract

Abstract Light intensity modulation is crucial for the development of optical imaging, optical sensing, and optical switch. Light intensity modulation methods, such as changing structural parameters, external temperature, or external voltage, make the control process time consuming and complex. The plasmonic polarization modulation is an effective strategy to modulate the light intensity, but this method is limited by the excitation of surface plasmons with transverse magnetic (TM) polarized light. Herein, we report another polarization modulation method for light intensity based on guided mode resonance in a dielectric grating excited by transverse electric (TE) polarized light. The nanosystem comprises a Si grating and a TiN substrate. By adjusting the polarization states of the incident light from TE to TM, the proposed nanosystem exhibits an outstanding light intensity modulation performance with a relative modulation depth of 25833%. The presented method provides another way for modulating the light intensity, which has potential applications in optical switching, optical imaging, and optical anti-counterfeiting.