Adiabatic polarization rotator combiner
View Patent ↗A system may include a polarization rotator combiner. The polarization rotator combiner may include a first stage, a second stage, and a third stage. The first stage may receive a first component of light with a TE00 polarization and a second component of light with the TE00 polarization. The first stage may draw optical paths of the first and second components together. The second stage may receive the first component and the second component from the first stage. The second stage may convert the polarization of the second component from the TE00 polarization to a TE01 polarization. The third stage may receive the first component and the second component from the second stage. The third stage may convert polarization of the second component from the TE01 polarization to a TM00 polarization. The third stage may output the first component and output the second component.
1. A system comprising a polarization rotator combiner (PRC) that includes:
a first stage configured to:
receive a first component of light with a TE00 polarization in a first input of the PRC and receive a second component of light with the TE00 polarization in a second input of the PRC;
output the first component with the TE00 polarization via a first intermediate output; and
output the second component with the TE00 polarization via a second intermediate output different than the first intermediate output, wherein a distance between the first and second intermediate output is less than a distance between the first and second input;
a second stage configured to:
receive from the first stage the first component with the TE00 polarization and the second component with the TE00 polarization;
convert the polarization of the second component from the TE00 polarization to a TE01 polarization; and
output the first component with the TE00 polarization and the second component with the TE01 polarization;
a third stage configured to:
receive from the second stage the first component with the TE00 polarization and the second component with the TE01 polarization;
convert polarization of the second component from the TE01 polarization to a TM00 polarization; and
output the first component with the TE00 polarization and output the second component with the TM00 polarization from an output of the PRC;
a waveguide core that includes a first ridge that extends above a rib through each of the first, second, and third stages.
2. The system of claim 1 , wherein the first component and the second component include light with a wavelength between 1,260 nanometers (nm) and 1,340 nm.
3. The system of claim 1 , wherein the first component includes a first combined component with first and second wavelength channels and the second component includes a second combined component with third and fourth wavelength channels.
4. The system of claim 1 , further comprising an optical fiber optically coupled to the third stage of the PRC through the output of the PRC.
5. The system of claim 1 , wherein the waveguide core includes the rib in each of the first, second, and third stages.
6. The system of claim 5 , wherein the waveguide core further comprises:
a second ridge that extends above the rib and that extends through each of the first and second stages, the second ridge laterally spaced apart from the first ridge in each of the first and second stages.
7. The system of claim 1 , wherein:
the rib tapers outward for a first portion of the first stage to a first width and has the first width as a constant width for a second portion of the first stage;
the rib has the first width as a constant width in the second stage;
the rib tapers from the first width inward for a first portion of the third stage to a second width, has the second width as a constant width for a second portion of the third stage, and tapers from the second width inward for a third portion of the third stage.