New 'negative light' method hides data in thermal background
Mar 9th 2026
A proof of concept from UNSW and Monash uses 'negative luminescence' to make thermal signals look like background heat so only a receiver with the right equipment can detect the hidden data.
- Researchers at UNSW Sydney and Monash use negative luminescence in the mid-infrared to conceal data transfers.
- The system encodes information with thermoradiative diodes that modulate thermal output to match background heat radiation.
- Lab tests achieved about 100 kilobytes per second and researchers expect megabit to gigabit speeds with improved emitters and materials.
- To outside observers the transmission blends into thermal noise and appears absent, making detection and interception difficult.
- Transmissions can also be encrypted conventionally for an added layer of security.
- The team published the work in Light Science and Applications and is exploring less toxic semiconductors and graphene to improve performance.