Optimization of sawtooth surface-relief gratings: effects of substrate refractive index and polarization

View/ Open
Date
2006-05Author
Wu, Shun-Der
Gaylord, Thomas K.
Glytsis, Elias N.
Metadata
Show full item recordAbstract
The effect of the refractive index of the substrate together with the incident polarization on the optimization of sawtooth surface-relief gratings (SRGs) is investigated. The global optimum diffraction efficiencies of the −1st forward-diffracted order of sawtooth SRGs are 63 .3% occurring at n ₂ =1.47 for TE polarization and 73.8% occurring at n ₂ =2.88 for TM polarization. Incident TE polarization has higher optimum diffraction efficiency than TM polarization for all n ₂ <1.85 . In contrast, TM polarization has higher optimum diffraction efficiency than TE polarization for all n ₂ >1.85 . A polymer (n ₂ =1.5) optimum sawtooth SRG exhibits 62.6% efficiency for TE polarization. A silicon (n ₂ =3.475) optimum sawtooth SRG exhibits 68.6% efficiency for TM polarization. These sawtooth SRGs are compared to right-angle-face trapezoidal SRGs. It is found that the optimum profiles of right-angle-face trapezoidal SRGs have only very slightly increased efficiencies over sawtooth SRGs (0.04% for TE and 0.55% for TM).
Collections
- COPE Publications [376]