Patterned dielectric mirrors for uniformly high reflection in polarized light

Abstract

Two types of multilayered dielectric mirrors with high reflection in the visible range are fabricated on line-patterned substrates using a suitable combination of cost-effective soft lithography and RF magnetron sputtering. They are characterized at different visible wavelengths lying outside and inside their stopband range. Their response to linearly polarized incident light depends on the wavelength, angle of incidence, and the direction of orientation of the patterned lines on the substrate with respect to the direction of polarization. A comparison of these broadband high reflectors on patterned substrates with that of equivalent high reflectors on planar substrates confirmed that the patterned high reflectors have a much higher uniformity in their reflectance value when the polarization direction of incident light is changed, both within and outside their stopband range, even at oblique angles of incidence. These broadband high reflectors are useful in applications that require uniformly high reflection even while there are changes in wavelength, polarization and the angle of incidence.