Data storage and security are among the biggest challenges our technology-dependent world faces today, pushing us to explore unconventional options. The good news is that researchers worldwide are actively seeking novel solutions to address these problems.
One promising development comes from researchers at UNSW Sydney and Monash University, who have recently developed a system that conceals data transmissions in plain sight using a phenomenon called “negative luminescence.”
The result is a communication method that could be nearly impossible to hack, not because the message is encrypted, but because no one can even tell that a message is being sent.
The system works by blending signals into the natural heat radiation that everything around us constantly emits, the kind you see through a thermal camera. To any outside observer, it looks like nothing is happening at all, and only a receiver with the right equipment can detect and decode the hidden message.
What is negative luminescence?
Everything emits a faint glow of heat in the infrared spectrum. Negative luminescence makes that glow appear darker instead of brighter. Dr. Michael Nielsen, lead author from UNSW’s School of Photovoltaic and Renewable Energy Engineering, describes it as “a flashlight that can go darker than off.” While that’s impossible with visible light, there are materials that can create this effect in the infrared range.
The team uses a device called a thermoradiative diode, which rapidly switches between brighter and darker-than-usual states. This creates a pattern hidden within background heat noise, making the transmission invisible to anyone unaware that data is being sent.
What could this mean for the real world?
In lab experiments, the team has achieved data transfer speeds of about 100 kilobytes per second. While this is modest for now, researchers believe the technology could eventually reach speeds of gigabytes per second as improvements are made to the emitter technology.
Colleagues at Monash University have already suggested that using graphene could push speeds to hundreds of gigabytes per second. If and when this happens, it will change the face of secure data transmission, making it almost impossible for hackers to get access to sensitive data.
