Analytical modeling for eliminating the 0th order by a tantalum oxide ridges grating

In this paper, using rigorous coupled-wave analysis, a beam splitter for eliminating 0th order by tantalum oxide ridges grating is proposed. The grating has a thinner structure of tantalum oxide grating ridges. At a normal incident light of.= 1550 nm, the grating can achieve the high efficiencies of the +/- 1st orders of 48.79%, 48.18% for transverse electric, transverse magnetic polarization and the 0th order of less than 1% for both polarizations. Besides, the grating has not only a good manufacturing tolerance in grating period d and duty cycle f but also a wide spectral bandwidth of 60 nm.