Polarization-independent broadband dielectric bilayer gratings for spectral beam combining system

摘要: Abstract We report on a polarization-independent all-dielectric trapezoidal bilayer grating with broadband and high diffraction efficiency. The ridge reflector consists of an HfO2 layer SiO2 layer. theoretical −1st order efficiencies the are more than 95% wavelength range from 1010 nm to 1080 nm for both TE TM polarizations. fabrication tolerances depending depths enough obtain designed using current craft. fabricated exceeding 94% efficiency 1000 nm 1085 nm measured by non-polarization laser has been applied in spectral beam combining external cavity combine eight beams into one output 10.77 kW.