Patent US10312387

Single photon detection using a resonator with an absorber
[+] Show Details

US10312387

1. An apparatus for detecting a signal photon at a first wavelength, the apparatus comprising: (8) (3)

a resonator to store a plurality of probe photons at a second wavelength different from the first wavelength;

an absorber, disposed at least partially in the resonator and substantially transparent to the plurality of probe photons, to absorb the signal photon, absorption of the signal photon causing a change of a resonant wavelength of the resonator, the change of the resonant wavelength causing release of at least some of the plurality of probe photons from the resonator; and

a detector, in optical communication with the resonator, to generate an electrical signal in response to detection of the at least some of the plurality of probe photons, the electrical signal indicating a presence of the signal photon.

2. The apparatus of claim 1, wherein the resonant wavelength of the resonator is substantially equal to or greater than 1.5 μm. (0)

3. The apparatus of claim 1, wherein the resonator has a quality factor greater than 10⁴. (0)

4. The apparatus of claim 1, wherein the resonator comprises a first distributed Bragg reflector (DBR) and a second DBR disposed opposite the first DBR. (2) (0)

5. The apparatus of claim 4, wherein the absorber comprises a semiconductor heterostructure disposed between the first DBR and the second DBR. (0)

6. The apparatus of claim 4, wherein the absorber is disposed between the first DBR and the second DBR, the absorber comprising: (1) (3)

a first semiconductor layer having a first bandgap;

a second semiconductor layer disposed on a first side of the first semiconductor layer; and

a third semiconductor layer disposed on a second side, opposite the first side, of the first semiconductor layer, the second semiconductor layer and the third semiconductor layer having a second bandgap greater than the first bandgap of the first semiconductor layer.

7. The apparatus of claim 6, wherein the first semiconductor layer comprises InGaN and the second semiconductor layer and the third semiconductor layer comprise GaN. (0)

8. The apparatus of claim 1, wherein the resonator comprises: (0) (2)

9. The apparatus of claim 1, wherein the resonator comprises: (1) (2)

an input waveguide; and

a micro-ring resonator, evanescently coupled to the input waveguide, to receive the plurality of probe photons via the input waveguide.

10. The apparatus of claim 9, wherein the input waveguide comprises: (0) (2)

11. The apparatus of claim 1, wherein the absorber comprises a III-N semiconductor. (0)

12. The apparatus of claim 1, wherein the absorber comprises a semiconductor having a bandgap energy at least two times greater than a photon energy of the probe photons in the plurality of probe photons. (0)

13. The apparatus of claim 1, wherein the resonator comprises: (0) (2)

14. A method of detecting a signal photon at a first wavelength, the method comprising: (5) (4)

coupling a plurality of probe photons at a second wavelength, different from the first wavelength, into a resonator, the resonator including an absorber disposed at least partially in the resonator and substantially transparent to the plurality of probe photons;

absorbing the signal photon with the absorber, the absorber changing a resonant wavelength of the resonator in response to absorption of the signal photon, thereby releasing at least some of the plurality of probe photons from the resonator; and

detecting the at least some of the plurality of probe photons; and

determining a presence of the signal photon based on detection of the at least some of the plurality of probe photons.

15. The method of claim 14, wherein coupling the plurality of probe photons into the resonator comprises transmitting the plurality of probe photons through a first DBR disposed opposite a second DBR and wherein absorbing the signal photon comprises coupling the signal photon into a semiconductor heterostructure disposed between the first DBR and the second DBR. (1) (0)

17. The method of claim 14, wherein coupling the plurality of probe photons comprises transmitting the plurality of probe photons through a first line defect in a photonic crystal to a photonic waveguide defined by a first point defect and a second point defect, and wherein detecting the at least some of the plurality of probe photons comprises transmitting the at least some of the plurality of probe photons through a second line defect in the photonic crystal to a detector. (0)

18. The method of claim 14, wherein coupling the plurality of probe photons comprises: (0) (2)

19. The method of claim 14, wherein absorbing the signal photon comprises absorbing the signal photon with a III-N semiconductor having a bandgap energy at least two times greater than a photon energy of the plurality of probe photons. (0)

20. The method of claim 14, wherein coupling the plurality of probe photons comprises transmitting the plurality of photons through a first reflector having a first reflectance less than 99.5% at the second wavelength and disposed opposite a second reflector and having a second reflectance greater than 99.9% at the second wavelength. (0)

21. A single-photon detector to detect a signal photon at a signal wavelength, the single-photon detector comprising: (0) (4)

an input waveguide to receive a plurality of probe photons at a probe wavelength less than half of the signal wavelength;

a micro-ring resonator, evanescently coupled to the input waveguide, to receive the plurality of probe photons, the input waveguide comprising: a first section, evanescently coupled to a first location of the micro-ring resonator, to couple out a first portion of the plurality of probe photons; and

a second section, evanescently coupled to a second location of the micro-ring resonator, to couple out a second portion of the probe photons, the second portion destructively interfering with the first portion;

an absorber, disposed at least partially in the micro-ring resonator and substantially transparent at the probe wavelength, to absorb the signal photon, absorption of the signal photon causing a change of a resonant wavelength of the micro-ring resonator releasing at least some of the plurality of probe photons from the micro-ring resonator, the absorber comprising a III-N semiconductor having a bandgap energy at least two times greater than a photon energy of the probe photons in the plurality of probe photons; and

a detector, in optical communication with the resonator, to detect the at least some of the plurality of probe photons.

View Abstract and Specification Size

PDF with Images and Document Face >

Full Text Publication >

Patent US10312387

Single photon detection using a resonator with an absorber

Patent Matrix® Search