St. Petersburg State University (SPbGU) has introduced a non-contact thermometer that uses neodymium-activated oxide nanoparticles. The device excels at measuring ultra-low temperatures, reaching as low as -253°C in space and other extreme environments. The development was reported by socialbites.ca and supported by a major research funding organization.
SPbGU notes that traditional contact-based temperature sensing becomes impractical in many scenarios — from processor chips and certain organs inside living beings to volcanic vents and interstellar space. In such cases, non-contact thermometry is preferred. The method relies on phosphors that absorb light and emit glow. The glow characteristics correlate with the surrounding medium and enable precise temperature determination. Yet, at very low temperatures, this optical approach faces efficiency challenges.
The Petersburg team tackled this limitation by introducing oxide nanoparticles activated by neodymium ions. A suspension of isopropyl alcohol and nanoparticle powder is prepared and applied to the surface of the object being measured. As the alcohol evaporates, a thin oxide layer remains attached to the surface. When illuminated with infrared light invisible to the naked eye, the particles glow in the infrared spectrum. This emission serves as the temperature signal, enabling accurate readings even at cryogenic temperatures.
Researchers highlight that the technology could support studies in low-temperature superconductivity and space exploration. For such applications, parts can be pre-treated with a phosphorus-based composition to optimize measurement fidelity in challenging environments.
Looking ahead, the team plans to widen the measurement range further, aiming for temperatures near the liquid helium limit of -268 °C. The work reflects ongoing efforts to create robust, non-contact sensing solutions for extreme conditions and space research.
In related efforts, researchers noted durable, clear coatings designed to shield satellite solar panels from micro-meteoroid impacts and space debris. This parallel line of work emphasizes the broader push for reliable, long-lasting instruments for space missions and high-tech settings.