Patent ID: 11949461
Assignee: BEIJING ZHONGKE GUOGUANG QUANTUM TECHNOLOGY CO., LTD.
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 1:
2. The integrated self-coherent receiving optical chip based on round-trip delay interferometers according to claim 1, wherein, the first round-trip delay interferometer comprises a second beam splitter, a fifth optical waveguide, a first delayed optical waveguide, a sixth optical waveguide and a fifth polarization beam splitting rotator;
the second beam splitter is configured to split the first signal light component to generate a first component and a second component with same amplitude;
the first delayed optical waveguide is configured to delay the first component by a length of half of an arm length difference of the first round-trip delay interferometer;
two output ports of the fifth polarization beam splitting rotator are directly connected by an optical waveguide, and are configured to reflect the first component from an incident port of the first component, and change a horizontal polarization component and a vertical polarization component of the first component into a vertical polarization component and a horizontal polarization component of the first component respectively; and configured to reflect the second component from an incident port of the second component, and change a horizontal polarization component and a vertical polarization component of the second component into a vertical polarization component and a horizontal polarization component of the second component respectively;
the second beam splitter is further configured to interfere the reflected first component and the reflected second component to generate the first interference optical signal and the second interference optical signal;
the second round-trip delay interferometer comprises a third beam splitter, a seventh optical waveguide, a second delayed optical waveguide, an eighth optical waveguide, a sixth polarization beam splitting rotator and a first quarter-wave plate,
wherein, an angle between a main axis of the first quarter-wave plate and a horizontal direction is 0°;
the third beam splitter is configured to split the second signal light component to generate a third component and a fourth component with a same amplitude;
the second delayed optical waveguide is configured to delay the third component by a length of half of an arm length difference of the second round-trip delay interferometer;
two output ports of the sixth polarization beam splitting rotator are directly connected by another optical waveguide, and are configured to reflect the third component from an incident port of the third component, and change a horizontal polarization component and a vertical polarization component of the third component into a vertical polarization component and a horizontal polarization component of the third component, respectively; and configured to reflect the fourth component from an incident port of the fourth component, and change a horizontal polarization component and a vertical polarization component of the fourth component into a vertical polarization component and a horizontal polarization component of the fourth component, respectively;
the another optical waveguide directly connecting the two output ports of the sixth polarization beam splitting rotator is provided with the first quarter-wave plate that is configured to increase the fourth component by π/2 phase, and not increase a phase of the third component; and
the third beam splitter is further configured to interfere the reflected third component and the reflected fourth component to generate the third interference optical signal and the fourth interference optical signal.