Method for generating non-classical light from classical light
Non-classical light is generated from classical light by providing a non-classical light generation stage with at least one waveguide; inputting classical light into the non-classical light generation stage; and converting at least part of the classical light into non-classical light. The classical light is in a non-fundamental propagation mode of a waveguide of the non-classical light generation stage, and the non-classical light is in a fundamental propagation mode a waveguide of the non-classical light generation stage. The converting does not involve quasi-phase-matching. An input adaptation stage obtains classical light for input into the non-classical light generation stage. In the input adaptation stage, classical light is converted into classical light of a different waveguide propagation mode. A system has a non-classical light generation stage for converting classical light at least partly into non-classical light, and an optical switch and/or an optical phase shifter, arranged on a single optical chip.
1 . A method for generating non-classical light from classical light, the method comprising the steps of:
providing a non-classical light generation stage comprising at least one waveguide,
providing an input adaptation stage with a waveguide that continues as the waveguide of the non-classical light generation stage,
converting in the input adaptation stage classical light into classical light of a different waveguide propagation mode,
inputting the classical light of a different waveguide propagation mode into the non-classical light generation stage, and
converting in the non-classical light generation stage at least part of the classical light into non-classical light,
wherein the classical light is in a non-fundamental propagation mode of the waveguide of the non-classical light generation stage and the non-classical light is in a fundamental propagation mode of the waveguide of the non-classical light generation stage.
2 . The method of claim 1 , wherein in the non-classical light generation waveguide, the classical light is of a first wavelength and the non-classical light is of a second wavelength different from the first wavelength.
3 . The method of claim 1 , wherein the non-classical light generation waveguide's effective refractive index for the classical light injected into the non-classical light generation waveguide is identical to the non-classical light generation waveguide's effective refractive index for the non-classical light.
4 . The method of claim 1 , wherein a waveguide of the non-classical light generation stage has a thickness of between 300 and 500 nm.
5 . An apparatus for generating non-classical light from classical light, the apparatus comprising a non-classical light generation stage for converting classical light at least partly into non-classical light, wherein the apparatus comprises an input adaptation stage for converting classical light into classical light of a different waveguide propagation mode, the input adaptation stage being arranged upstream of the non-classical light generation stage such that the converted light obtained in the input adaptation stage can be input into the non-classical light generation stage for converting it at least partly into non-classical light, wherein a waveguide of the input adaptation stage continues as a waveguide of the non-classical light generation stage.