A complete theoretical analysis of a modified grating-frustrated coupler involving a second grating in an input channel is presented. We show that this second grating allows for improved performance of the device, especially in terms of backreflected light. The condition for zero backreflection is found analytically, and a physical interpretation of the results is given.
© 2003 Optical Society of America
Ararat Yesayan and Réal Vallée, "Zero backreflection condition for a grating-frustrated coupler," J. Opt. Soc. Am. B 20, 1418-1426 (2003)