Wavelength-scale optical parametric oscillators

1. A device, comprising:

one or more optical parametric oscillators (OPOs), each of the OPOs comprising:

a resonator comprising a material having a nonlinear susceptibility generating an output electromagnetic field in response to a pump electromagnetic field inputted into the material, wherein:

the output electromagnetic field has one or more output wavelengths longer than one or more pump wavelengths of the pump electromagnetic field, and

the resonator has dimensions wherein a largest of the dimensions is:

less than 10 microns, and

within a factor of 2 of the one or more output wavelengths in free space.

2. The device of claim 1 , wherein the resonator comprises a particle having the dimensions.

3. The device of claim 1 , wherein the resonator fits within a sphere or spherical volume having a radius of 5 microns.

4. The device of claim 1 , wherein the resonator supports one or more quasi normal electromagnetic modes of at least one of the pump electromagnetic field or the output electromagnetic field.

5. The device of claim 4 , wherein the quasi normal electromagnetic modes comprise one or more multi polar Mie resonances comprising the output electromagnetic field.

6. The device of claim 4 , further comprising a disk comprising the resonator, a cylinder comprising the resonator, or a sphere comprising the resonator.

7. The device of claim 1 , wherein the material comprises at least one of a metal, a dielectric, a semiconductor, or a polymer.

8. The device of claim 1 , wherein the resonator supports one or more plasmonic modes of at least one of the pump electromagnetic field or the output electromagnetic field.

9. The device of claim 8 , comprising a plurality of the OPOs wherein the resonators are evanescently coupled or coupled through waveguides or auxiliary cavities.

10. The device of claim 8 , comprising a plurality of the OPOs outputting a plurality of output electromagnetic fields in response to a plurality of the pump electromagnetic fields, each of the pump electromagnetic fields can have at least one of a phase or an amplitude that is different from the phase or the amplitude of another of the pump electromagnetic fields.

11. The device of claim 1 , wherein the resonator comprises a structure including a gap that supports a plasmonic mode that overlaps with the material.

12. The device of claim 11 , further comprising an additional material having a second order nonlinear susceptibility on top of the gap.

13. The device of claim 1 , wherein the resonator includes an additional material having a different dielectric constant than the material, so as to increase an efficiency of a parametric interaction of the pump electromagnetic field and the output electromagnetic field as compared to without the additional material.

14. The device of claim 13 , wherein:

the resonator includes a plurality of regions or pixels including different dielectric constants and thicknesses arranged to tailor an overlap of the pump electromagnetic field and the output electromagnetic field, and

the additional material comprises at least one of a polymer, a glass, a linear material, or an index of refraction less than 2.

15. A photonic integrated circuit including one or more of the resonators of claim 1 .

16. The photonic integrated circuit of claim 15 , further comprising a source of the pump electromagnetic field at a location off the photonic integrated circuit and having a free space coupling to the resonator, wherein the photonic integrated circuit does not include a fiber coupling or waveguide coupling the pump electromagnetic field applied from the free space.

17. A sensor, comprising:

a network including a plurality of the OPOs of claim 1 ; and

one or more detectors coupled to detect the output electromagnetic field, thereby sensing at least one of the pump electromagnetic field or an environment around the network via a detection of the output electromagnetic field by the detector.

18. An optical computer, comprising:

a network including a plurality of the OPOs of claim 1 ; and

couplings between the OPOs, wherein the couplings are adjusted to model an array of coupled spins, so that a minimum threshold of each of the OPOs corresponds to a minimum energy configuration of one of the coupled spins in the array.

19. The device of claim 1 , wherein the largest of the dimensions comprises at least one of a dimeter, a width, a length, or a height.

20. A method of operating an optical parametric oscillator (OPO), comprising:

inputting a pump electromagnetic field into a resonator comprising a material having a nonlinear susceptibility generating an output electromagnetic field in response to the pump electromagnetic field, wherein:

the output electromagnetic field has one or more output wavelengths longer than one or more pump wavelengths of the pump electromagnetic field, and

the resonator has dimensions wherein a largest of the dimensions is less than 10 microns and within a factor of 2 of the one or more output wavelengths in free space, and wherein the OPO is configured for at least one of the following:

the OPO operating at degeneracy such that at least one of the output wavelengths is twice at least one of the pump wavelengths,

the output electromagnetic field comprises a frequency comb comprising a set of equidistant frequency peaks,

the output electromagnetic field has an output spectrum broader than an input spectrum of the pump electromagnetic field, in frequency units measured at the 30-dB level below the peak, or

the pump electromagnetic field comprising a continuous wave, a time-varying, or a pulsed electromagnetic field.

21. A method of making an optical parametric oscillator, comprising:

providing a resonator comprising a material having a nonlinear susceptibility generating an output electromagnetic field in response to a pump electromagnetic field inputted into the material, wherein:

the output electromagnetic field has one or more output wavelengths longer than one or more pump wavelengths of the pump electromagnetic field, and

the resonator has dimensions, wherein a largest of the dimensions is less than 10 microns and within a factor of 2 of the one or more output wavelengths in free space.