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US-12625007-B2 - Optomechanically calibrated photonic thermometer and calibrating a photonic thermometer

US12625007B2US 12625007 B2US12625007 B2US 12625007B2US-12625007-B2

Abstract

A thermometer system includes a photonic thermometer; and an optomechanical thermometer configured to calibrate the photonic thermometer, thereby making the thermometer system an optomechanically calibrated photonic thermometer.

Inventors

  • Daniel Schaeder Barker
  • Nikolai Nikolaevich Klimov
  • Thomas Patrick Purdy

Assignees

  • GOVERNMENT OF THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF COMMERCE

Dates

Publication Date
20260512
Application Date
20240403

Claims (15)

  1. 1 . A nanophotonic thermometer system comprising: a photonic thermometer; and an optomechanical thermometer configured to calibrate the photonic thermometer, thereby making the thermometer system an optomechanically calibrated photonic thermometer.
  2. 2 . The nanophotonic thermometer system of claim 1 , wherein the optomechanical thermometer is a fin-type optomechanical oscillator.
  3. 3 . The nanophotonic thermometer system of claim 2 , further comprising: a bus waveguide; and a secondary layer of photoresist or dielectric oxide deposited onto the bus waveguide, the photonic thermometer, and the fin-type optomechanical thermometer.
  4. 4 . The nanophotonic thermometer system of claim 2 , further comprising: a bus waveguide; and a silicon oxide substrate etched down beneath the bus waveguide, the photonic thermometer, and the fin-type optomechanical thermometer.
  5. 5 . The nanophotonic thermometer system of claim 1 , wherein the photonic thermometer is a photonic crystal cavity.
  6. 6 . The nanophotonic thermometer system of claim 1 , wherein the photonic thermometer is a ring resonator.
  7. 7 . The nanophotonic thermometer system of claim 1 , wherein the photonic thermometer is a disk resonator.
  8. 8 . The nanophotonic thermometer system of claim 1 , further comprising a temperature control device integrated on-chip with the photonic thermometer and the optomechanical thermometer.
  9. 9 . A method of calibrating a nanophotonic thermometer system comprising: activating a temperature control device of the nanophotonic thermometer system; adjusting the temperature control device while iteratively measuring a relative temperature of the nanophotonic thermometer system until a photonic thermometer provides a fixed resonance frequency response; and measuring an absolute temperature of the nanophotonic thermometer system using an optomechanical thermometer; and calibrating the photonic thermometer using the absolute temperature measurement and a stable relative temperature measurement.
  10. 10 . The method of claim 9 , further comprising the step of changing to a different stable resonance frequency response of the photonic thermometer by adjusting the temperature control device.
  11. 11 . A method of calibrating a nanophotonic thermometer system comprising: measuring a relative temperature of a sample using a photonic thermometer; measuring an absolute temperature of the sample using an optomechanical thermometer; and calibrating the photonic thermometer using the absolute temperature measurement and the relative temperature measurement.
  12. 12 . The method of claim 11 , further comprising the steps of: removing the nanophotonic thermometer system from a process environment at a predetermined calibration interval; placing the nanophotonic thermometer system in a bath environment; and returning the nanophotonic thermometer system to the process environment after the step of calibrating.
  13. 13 . The method of claim 12 , further comprising the step of changing a temperature of the bath environment or moving the nanophotonic thermometer system into a different bath environment at a different temperature.
  14. 14 . A method of operating a nanophotonic thermometer system comprising the steps of: operating the nanophotonic thermometer system in a process environment; measuring a relative temperature of a sample using a photonic thermometer of the nanophotonic thermometer system; measuring an absolute temperature of the sample using an optomechanical thermometer of the nanophotonic thermometer system; comparing the absolute temperature measurement and the relative temperature measurement; and if the measurements disagree, correcting the calibration of the photonic thermometer, and if the measurements agree, continuing operation without correction.
  15. 15 . The method of claim 14 , further comprising the step of: if the measurements disagree, removing the nanophotonic thermometer system from the process environment; placing the nanophotonic thermometer system in a bath environment; measuring a relative temperature of the bath environment using the photonic thermometer; measuring an absolute temperature of the bath environment using the optomechanical thermometer; and calibrating the photonic thermometer using the absolute temperature measurement of the bath environment and the relative temperature measurement of the bath environment.

Description

RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application Ser. No. 63/456,604 (filed Apr. 3, 2023), which is herein incorporated by reference in its entirety. FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT This invention was made with United States Government support from the National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce. The Government has certain rights in this invention. COPYRIGHT NOTICE This patent disclosure may contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the U.S. Patent and Trademark Office patent file or records, but otherwise reserves any and all copyright rights. FIELD OF INVENTION The present invention relates generally to miniaturized thermometers, and more particularly to combining the benefits of a photonic thermometer and a optomechanical thermometer. BACKGROUND Thermometry is the science of measuring temperature. Temperature is a measure of the average kinetic energy of the particles in a system. The higher the temperature, the faster the particles are moving. There are many different methods for measuring temperature. Some common methods include: Resistance thermometers: These thermometers measure the change in resistance of a material as a function of temperature.Thermocouples: These thermometers measure the voltage generated by the junction of two different materials as a function of temperature.Liquid-in-glass thermometers: These thermometers measure the expansion of a liquid as a function of temperature.Infrared thermometers: These thermometers measure the intensity of infrared radiation emitted by an object as a function of temperature. SUMMARY OF INVENTION Each of these methods has its own advantages and disadvantages. Resistance thermometers are accurate and stable, but they can be slow to respond to changes in temperature. Thermocouples are fast and have a wide temperature range, but they can be inaccurate. Liquid-in-glass thermometers are inexpensive and easy to use, but they are not very accurate or stable. Infrared thermometers are fast and accurate, but they can be affected by the emissivity of the object being measured. Furthermore, resistance thermometers, liquid-in-glass, and infrared thermometers drift over time and all require frequent recalibrations. According to one aspect of the invention, a nanophotonic thermometer system includes a photonic thermometer; and an optomechanical thermometer configured to calibrate the photonic thermometer, thereby making the thermometer system an optomechanically calibrated photonic thermometer. Such thermometer calibrates itself without taking it out of service. Optionally, the optomechanical thermometer is a fin-type optomechanical oscillator. Optionally, the photonic thermometer is a photonic crystal cavity. Optionally, the photonic thermometer is a ring resonator. Optionally, the photonic thermometer is a disk resonator. Optionally, the nanophotonic thermometer system also includes a bus waveguide and a secondary layer of photoresist or dielectric oxide deposited onto the bus waveguide, the photonic thermometer, and the fin-type optomechanical thermometer. Optionally, the nanophotonic thermometer system includes a bus waveguide and a silicon oxide substrate etched down beneath the bus waveguide, the photonic thermometer, and the fin-type optomechanical thermometer. According to another aspect of the invention, a method of calibrating a nanophotonic thermometer system includes measuring a relative temperature of a sample using a photonic thermometer; measuring an absolute temperature of the sample using an optomechanical thermometer; and calibrating the photonic thermometer using the absolute temperature measurement and the relative temperature measurement. Optionally, the method includes removing the nanophotonic thermometer system from a process environment at a predetermined calibration interval; placing the nanophotonic thermometer system in a bath environment; and returning the nanophotonic thermometer system to the process environment after the step of calibrating. Optionally, the method includes changing a temperature of the bath environment or moving the nanophotonic thermometer system into a different bath environment at a different temperature. Optionally, the method includes in situ calibration without the need either of removing the photonic thermometer, or the need of external temperature bath, during which a fixed temperature is established using an on-chip integrated temperature control micro-element such as, for example, a resistive micro heater imbedded in the photonic chip in immediate proximity next to photonic and optomechanical thermometers, a Peltier miniature heater/cooler module and/or a Joule-Thomson micro-cooler, located in the immediate proximity next to the ph