Photonic bolometer and performing broadband high-absorption photonic bolometry

Patent metadata

Field	Value
Publication number	US-12345573-B2
Application number	US-202217957817-A
Country	US
Kind code	B2
Filing date	Sep 30, 2022
Priority date	Sep 25, 2020
Publication date	Jul 1, 2025
Grant date	Jul 1, 2025

Abstract

A photonic bolometer includes: a photonic chip; a weak thermal link; a thermally-isolated member, and the weak thermal link thermally isolates the thermally-isolated member from the photonic chip; a photonic temperature sensor; a chip waveguide in optical communication with the photonic temperature sensor; and a photon absorber that receives incident radiation light, increases temperature due to absorption of the incident radiation light, heats the photonic temperature sensor in response to receipt of the incident radiation light, and changes the resonance frequency of the photonic temperature sensor in response to receiving the incident radiation light.

First claim

What is claimed is:

1. A photonic bolometer for performing broadband high-absorption photonic bolometry, the photonic bolometer comprising:
a photonic chip;
a weak thermal link disposed on and in mechanical communication with the photonic chip;
a thermally-isolated member disposed on the weak thermal link and in mechanical communication with the weak thermal link, such that the weak thermal link is interposed between the thermally-isolated member and the photonic chip, and the weak thermal link thermally isolates the thermally-isolated member from the photonic chip;
a photonic temperature sensor disposed on the thermally-isolated member and comprising a resonance frequency from which a temperature of the thermally-isolated member is determinable and that varies with temperature of the thermally-isolated member, wherein the photonic temperature sensor receives primary probe light from a chip waveguide and produces a bolometer light from the primary probe light;
the chip waveguide disposed on the thermally-isolated member in optical communication with the photonic temperature sensor and that communicates the primary probe light to the photonic temperature sensor and that monitors transmission and storage of the primary probe light by the photonic temperature sensor, wherein the chip waveguide receives the bolometer light from the photonic temperature sensor to determine the temperature of the thermally-isolated member via a change in resonance frequency of the photonic temperature sensor; and
a photon absorber disposed on the thermally-isolated member in thermal communication with the photonic temperature sensor and that receives incident radiation light, increases temperature due to absorption of the incident radiation light, heats the photonic temperature sensor in response to receipt of the incident radiation light, and changes the resonance frequency of the photonic temperature sensor in response to receiving the incident radiation light.

2. The photonic bolometer of claim 1 , further comprising an isolation trench bounded by the photonic chip and the thermally-isolated member, such that the isolation trench is interposed between the photonic chip and the thermally-isolated member.

3. The photonic bolometer of claim 2 , wherein the isolation trench surrounds the thermally-isolated member.

4. The photonic bolometer of claim 1 , further comprising a reference phonic thermometer disposed on the photonic chip to measures a temperature of the substrate.

5. The photonic bolometer of claim 1 , wherein the weak thermal link mechanically interconnects the thermally-isolated member and the photonic chip.

6. The photonic bolometer of claim 1 , further comprising an undercut arranged between the substrate and the thermally-isolated member.

7. The photonic bolometer of claim 6 , wherein the undercut spaces apart the substrate and the thermally-isolated member so that the chip waveguide, the photonic temperature sensor, and the photon absorber are suspended above and relative to the substrate, with the chip waveguide extending from opposing portions of an oxide dielectric, which are interposed between the chip waveguide and the substrate, over the substrate, and the photon absorber is disposed on the photonic temperature sensor.

8. The photonic bolometer of claim 1 , wherein the photonic temperature sensor is interposed between the chip waveguide and the photon absorber.

9. The photonic bolometer of claim 1 , wherein the photonic temperature sensor and the photon absorber are disposed proximate to the chip waveguide, and the photon absorber is disposed on the photonic temperature sensor so that the photonic temperature sensor is interposed between the photon absorber and the thermally-isolated member.

10. The photonic bolometer of claim 1 , wherein the photonic chip, the thermally-isolated member, and the weak thermal link independently comprise a semiconductive material.

11. The photonic bolometer of claim 1 , wherein the photonic temperature sensor comprises a photonic crystal cavity, a ring resonator, or a disk resonator, such that the resonance frequency of the photonic temperature sensor is sensitive to temperature.

12. The photonic bolometer of claim 1 , further comprising a cladded dielectric disposed on the photonic temperature sensor, such that the photonic temperature sensor is interposed between the cladded dielectric and the substrate.

13. The photonic bolometer of claim 1 , wherein the photonic temperature sensor comprises a semiconductive material.

14. The photonic bolometer of claim 1 , wherein the photon absorber comprises vertically alinged carbon nanotubes.

15. The photonic bolometer of claim 1 , wherein the weak thermal link, the thermally-isolated member, the photonic temperature sensor, and the photon absorber are arranged as a single photonic bolometric pixel in the photonic bolometer.

16. The photonic bolometer of claim 15 , further comprising additional photonic bolometric pixels arranged in an array.

17. The photonic bolometer of claim 16 , wherein the chip waveguide extends along the photonic bolometer so that the chip waveguide is in optical communication with each photonic temperature sensor in each photonic bolometric pixel and:
communicates primary probe light to each photonic temperature sensor in each photonic bolometric pixel; and
receives bolometer light from each photonic temperature sensor in each photonic bolometric pixel,
such that the at least a two-dimensional termperature map is obtained across the photonic bolometer from the bolometer light from each photonic temperature sensor in each photonic bolometric pixel.

18. A photonic bolometry system, comprising:
a probe light source that receives a control light signal and produces a primary probe light based on the control light signal;
a photonic bolometer in optical communication with the probe light source and that receives the primary probe light from the probe light source, receives incident radiation light, and produces ref a 244 from the ref a 206 in response to receiving the incident radiation light, the photonic bolometer comprising:
a photonic chip;
a weak thermal link disposed on and in mechanical communication with the photonic chip;
a thermally-isolated member disposed on the weak thermal link and in mechanical communication with the weak thermal link, such that the weak thermal link is interposed between the thermally-isolated member and the photonic chip, and the weak thermal link thermally isolates the thermally-isolated member from the photonic chip;
a photonic temperature sensor disposed on the thermally-isolated member and comprising a resonance frequency from which a temperature of the thermally- isolated member is determinable and that varies with temperature of the thermally- isolated member, wherein the photonic temperature sensor receives primary probe light from a chip waveguide and produces a bolometer light from the primary probe light;
the chip waveguide disposed on the thermally-isolated member in optical communication with the photonic temperature sensor and that communicates the primary probe light to the photonic temperature sensor and that monitors transmission and storage of the primary probe light by the photonic temperature sensor, such that the chip waveguide receives the primary probe light from the probe light source, receives the bolometer light from the photonic temperature sensor, and communicates the bolometer light to a photodetector; and
a photon absorber disposed on the thermally-isolated member in thermal communication with the p

Assignees

• Government Of The Us Secretary Of Commerce

Inventors

• Klimov Nikolai Nikolaevich
• Tomlin Nathan Andrew
• Yung Christopher Shing-Yu

Classifications

• G01J5/0818 Primary

  Waveguides · CPC title

• G01J5/0853

  having infrared absorbers other than the usual absorber layers deposited on infrared detectors like bolometers, wherein the heat propagation between the absorber and the detecting element occurs within a solid · CPC title

• G01J5/20

  using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices · CPC title

• G01J5/58 Primary

  using absorption; using extinction effect · CPC title