Single polarization circulator

A method comprising:

• receiving, at a first port of a first polarization splitter, a first optical signal;
• receiving, at a first port of a first optical circuit optically coupled to the first polarization splitter, a second optical signal, wherein the first optical circuit comprises a first plurality of phase shifters;
• and
• adjusting by a first controller, the first plurality of phase shifters such that (i) the first optical circuit outputs the first optical signal at a second port of the first optical circuit, (ii) the first plurality of phase shifters separate the second optical signal into a first component and a second component, (iii) the first plurality of phase shifters direct the first component to a second port of the first polarization splitter and the second component to a third port of the first polarization splitter, and (iii) the first polarization splitter produces the second optical signal using the first and second components and outputs the second optical signal at the first port of the first polarization splitter.

A photonic chip comprising:

• a polarization splitter arranged to receive a first optical signal at a first port of the polarization splitter;
• a first multiplexer arranged to receive a first output from the polarization splitter;
• a second multiplexer arranged to receive a second output from the polarization splitter;
• and
• a first optical circuit optically coupled to the first multiplexer and the second multiplexer and arranged to receive a second optical signal at a first port of the first optical circuit, the first optical circuit comprising a plurality of phase shifters arranged such that (i) the first optical circuit outputs, at a second port of the first optical circuit, the first optical signal, (ii) the plurality of phase shifters separate the second optical signal into a first component and a second component, (iii) the first multiplexer directs the first component to a second port of the polarization splitter and the second multiplexer directs the second component to a third port of the polarization splitter, and (iii) the polarization splitter produces the second optical signal using the first and second components and outputs, at the first port of the polarization splitter, the second optical signal.