Scientists at the Institute of Physics, Nicolaus Copernicus University (UMK), have developed a new method formeasuring temperature and gas concentration using light alone, without physical contact or calibration.
The achievement by researchers at Nicolaus Copernicus University in Toruń opens up new possibilities for highly precise, contactless measurements in science, industry, and environmental monitoring. The results of the research and potential applications are published in the renowned journal Physical Review Letters. The authors of the article “Leveraging Resonant Frequencies of an Optical Cavity for Spectroscopic Measurement of Gas Temperature and Concentration” are: Prof. Daniel Lisak, M.Sc. Vittorio D’Agostino, Dr. Szymon Wójtewicz, Dr. Agata Cygan, Prof. UMK, M.Sc. Marcin Gibas, Prof. Piotr Wcisło, Prof. Roman Ciuryło, and Dr. Katarzyna Bielska, Prof. UMK from the Institute of Physics at UMK.
By analyzing how carbon monoxide molecules shift resonances within an optical cavity, the scientists determined the gas temperature with exceptional precision—the measurement uncertainty was only 82 parts per million. This method works even at relatively high pressures, where previous optical techniques faced difficulties.
Instead of measuring the amount of absorbed light, the technique relies on how the resonant frequency of light inthe optical cavity changes due to interaction with the gas, making it less susceptible to errors in light intensity measurements, the researchers explain.
The same approach also allowed them to measure the gas concentration with a relative measurement uncertainty of 250 parts per million, which matches or exceeds standard contact sensors. Since this method is entirely based on the quantum properties of molecules and precise measurements of light frequency, it does not require regular calibration and can be extended to other gases, such as hydrogen, carbon dioxide, oxygen, and more. This, in turn, greatly expands the potential applications of the measurements not only in science but also in industry and satellite-based monitoring of Earth’s atmosphere.