Researchers in South Korea have developed a medium-infrared photodetector that operates stably at room temperature and can be mass-produced.
Professor Kim Sang-hyun of the Korea Advanced Institute of Science and Technology (KAIST) noted on the 27th that they have developed a medium-infrared photodetector technology that operates stably at room temperature. The results of this research were published on the 19th in the international journal "Light: Science & Applications."
Medium-infrared light is used to analyze molecules in the atmosphere of exoplanets. The James Webb Space Telescope of the National Aeronautics and Space Administration (NASA) also uses this range to reveal components such as water vapor and sulfur dioxide in exoplanets. To precisely analyze medium-infrared light, which has unique absorption spectra like fingerprints for each molecule, high-sensitivity photodetector technology capable of detecting weak light is needed.
However, existing medium-infrared photodetectors generate noise due to heat generated at room temperature, making a cooling system essential. This increases the size and expense of the equipment, complicating the miniaturization of sensors and applications in portable devices. In addition, existing medium-infrared photodetectors are not compatible with silicon processes, making mass production difficult and resulting in high manufacturing expenses, which has restricted commercialization.
In response, the research team successfully developed a new medium-infrared sensor that is perfectly compatible with existing processes and can operate without cooling. The key is the bolometer effect, which utilizes the principle that light is converted to heat upon hitting the sensor, causing changes in electrical signals based on temperature variations. This allows for the detection of the entire medium-infrared range, making it useful for real-time detection of various molecules.
The developed photodetector can also be mass-produced at low expense and operates stably at room temperature. In particular, the research team successfully detected carbon dioxide gases in real time using this technology, demonstrating its potential for various applications such as environmental monitoring and harmful gas analysis.
Professor Kim Sang-hyun stated, "This research represents a new approach that overcomes the limitations of existing medium-infrared photodetector technology and has high potential for practical applications in various fields in the future." He added, "In particular, as a sensor technology compatible with existing processes, it can be mass-produced at low expense, and will be actively utilized in next-generation environmental monitoring systems and smart manufacturing sites."
References
Light: Science & Applications (2025), DOI: https://doi.org/10.1038/s41377-025-01803-3