Generation of entangled photons in an optical Bragg resonator
Among other embodiments, a method for generated entangled photons is disclosed. The method comprises generating photons in a fundamental mode and converting the photons from the fundamental mode to a higher-order mode. The method further comprises generating, by a Bragg resonator configured to receive the photons, entangled photons in the fundamental mode from the converted photons in the higher-order mode. The method further comprises outputting the generated entangled photons from the Bragg resonator.
1. A photonics circuit, comprising:
a first optical coupler configured to receive photons and to convert the received photons from a fundamental mode to a higher-order mode;
a first Bragg resonator configured to receive the received photons from the first optical coupler, the first Bragg resonator comprising:
a first primary Bragg element configured to receive the photons in the higher-order mode;
a second primary Bragg element; and
at least one first waveguide separating the first primary Bragg element and the second primary Bragg element, wherein the at least one first waveguide is configured to generate entangled photons in the fundamental mode from the received photons in the higher-order mode,
wherein the first primary Bragg element and the second primary Bragg element are configured to reflect the received photons, and wherein at least one of the first primary Bragg element or the second primary Bragg element is configured to pass the generated entangled photons in the fundamental mode; and
at least one output port coupled to the first Bragg resonator, wherein the at least one output port is configured to output the generated entangled photons.
2. The photonics circuit of claim 1 , wherein the first primary Bragg element and the second primary Bragg element are configured to pass the generated entangled photons in the fundamental mode.
3. The photonics circuit of claim 1 , wherein the received photons propagate in the first Bragg resonator at a first wavelength, wherein the generated entangled photons propagate in the first Bragg resonator at a second wavelength, wherein the first Bragg resonator is resonant for the received photons at the first wavelength and not the second wavelength.
4. The photonics circuit of claim 1 , further comprising a second Bragg resonator, wherein the first Bragg resonator is nested within the second Bragg resonator, the second Bragg resonator comprising:
a first secondary Bragg element;
a second secondary Bragg element; and
at least one second waveguide coupled between the first secondary Bragg element; and the second secondary Bragg element,
wherein the second Bragg resonator is resonant for the generated entangled photons and not the received photons.
5. The photonics circuit of claim 4 , wherein the first and second secondary Bragg elements are positioned to generate an unequal rate of generated entangled photons output between the first primary Bragg element and the second primary Bragg element.
6. The photonics circuit of claim 1 , wherein the second primary Bragg element is configured to convert the received photons in the higher-order mode to the fundamental mode, and wherein the first primary Bragg element is configured to convert the received photons in the fundamental mode to the higher-order mode.
7. The photonics circuit of claim 1 , wherein the at least one output port comprises a first output coupler and a second output coupler, wherein the first output coupler is coupled to the first primary Bragg element, and wherein the second output coupler is coupled to the second primary Bragg element.
8. The photonics circuit of claim 1 , wherein the at least one output port comprises a circular configuration of waveguides that couples the outputs from the first primary Bragg element and the second primary Bragg element to a second optical coupler, wherein the circular configuration of waveguides functions as a resonator for the generated entangled photons.
9. A system, comprising:
a light source configured to generate pump photons in a fundamental mode;
a first optical coupler coupled to the light source and configured to receive the pump photons and to convert the received photons to a higher-order mode;
a first Bragg resonator configured to receive the pump photons from the first optical coupler, the first Bragg resonator comprising:
a first primary Bragg element configured to receive the pump photons in the higher-order mode;
a second primary Bragg element; and
at least one first waveguide separating the first primary Bragg element and the second primary Bragg element, wherein the at least one first waveguide is configured to generate entangled photons in the fundamental mode from the pump photons in the higher-order mode,
wherein the first primary Bragg element and the second primary Bragg element are configured to reflect the pump photons, and wherein at least one of the first primary Bragg element or the second primary Bragg element is configured to pass the generated entangled photons in the fundamental mode; and
at least one output port coupled to the first Bragg resonator, wherein the at least one output port is configured to output the generated entangled photons.
10. The system of claim 9 , wherein the light source, the first optical coupler, the first Bragg resonator, and the at least one output port are disposed on an integrated photonics chip.
11. The system of claim 9 , wherein the first optical coupler is configured to convert the pump light photons from the fundamental mode to a second-order mode.
12. The system of claim 11 , wherein the first optical coupler is an asymmetric directional coupler.
13. The system of claim 9 , wherein the first primary Bragg element and the second primary Bragg element are configured to pass the generated entangled photons in the fundamental mode.
14. The system of claim 9 , wherein the pump photons propagate in the first Bragg resonator at a first wavelength, wherein the generated entangled photons propagate in the first Bragg resonator at a second wavelength, wherein the first Bragg resonator is resonant for the pump photons at the first wavelength and not the second wavelength.
15. The system of claim 9 , further comprising a second Bragg resonator, wherein the first Bragg resonator is nested within the second Bragg resonator, the second Bragg resonator comprising:
a first secondary Bragg element;
a second secondary Bragg element; and
at least one second waveguide coupled between the first secondary Bragg element; and the second secondary Bragg element,
wherein the second Bragg resonator is resonant for the generated entangled photons and not the pump photons.
16. The system of claim 15 , wherein the first and second secondary Bragg elements are positioned to generate an unequal rate of generated entangled photons output between the first primary Bragg element and the second primary Bragg element.
17. The system of claim 9 , wherein the first optical coupler is positioned external to the first Bragg resonator.
18. The system of claim 9 , wherein the second primary Bragg element is configured to convert the received photons in the higher-order mode to the fundamental mode, and wherein the first primary Bragg element is configured to convert the received photons in the fundamental mode to the higher-order mode.
19. A method, comprising:
generating photons in a fundamental mode;
converting, by an optical coupler, the photons from the fundamental mode to a higher-order mode;
generating, by a Bragg resonator configured to receive the photons from the optical coupler, entangled photons in the fundamental mode from the converted photons in the higher-order mode;
outputting the generated entangled photons from the Bragg resonator.
20. The method of claim 19 , further comprising:
converting, from a first Bragg element of the Bragg resonator, the photons from the fundamental mode to the higher-order mode; and
converting, from a second Bragg element of the Bragg resonator, the photons from the higher-order mode to the fundamental mode.