Silicon-on-insulator ultra-compact duplexer based on a diffractive grating structure.

The use of a silicon-on-insulator diffractive grating structure is proposed to achieve ultra-compact duplexing operation. One-dimensional grating structures are proposed to spatially separate two wavelength bands. This device can become a key component in the fabrication of integrated optical transceivers for fiber-to-the-home applications, where a 1310nm wavelength channel and a 1490nm wavelength channel need to be duplexed. A 10mum x 10mum one-dimensional grating structure allows to spatially separate both wavelength bands on the photonic integrated circuit, with an average coupling efficiency of 55% and an optical bandwidth of 55-60nm. While these one-dimensional grating structures are strongly polarization dependent, a two-dimensional grating structure is presented to achieve polarization independent operation.