Polarization conversion Si waveguide Bragg grating for polarization independent wavelength filter

Si wire waveguide polarisation‐independent wavelength filter using polarisation rotation Bragg grating

“…A wide wavelength peak indicates high diffraction efficiency. The Bragg grating diffraction strength was estimated to be two times that of the device using the fundamental modes of [7]. The coupling coefficient of the Bragg grating was 0.033 μm −1 .…”

“…In this Letter, we propose a reflective Bragg grating that can convert the input polarisation into another polarisation of counter propagating light to achieve polarisation independence. We aimed at improving the diffraction efficiency compared to previous device using only fundamental mode [7].…”

“…Introduction: Optical filtering devices have been demonstrated using Si wire waveguide technology [1][2][3][4][5][6][7]. Polarisation manipulation is important in telecommunication systems.…”

Si waveguide polarisation rotation chirped Bragg grating

“…We have demonstrated that the polarisation insensitive wavelength filter can be obtained by using polarisation rotation Bragg diffraction [5–7]. A wavelength filter with flat‐top and wide transmission wavelength range can be obtained by grating with its period chirped along the propagation direction.…”

Polarisation rotation Bragg grating with high diffraction efficiency using Si waveguide top surface groove grating

“…We have demonstrated that the wavelength peaks and diffraction efficiencies of the TM and TE modes can be the same by usage of the polarisation rotation Bragg diffraction [5–7], irrespective of the waveguide size. The experimental polarisation rotation Bragg grating devices using a waveguide with non‐vertical side wall and rib waveguide structures have been reported.…”