True thermal invisibility would require a barrier that would split the heat flow, guide it around an object, and reunite it on the other side. The object inside would be protected from the external temperature gradient, while an observer outside would see the pattern expected from an uninterrupted material. In thermal terms, there would be no obvious object-shaped disturbance to detect. This is the trick the UIUC-led team says its new structure, detailed in the journal Nature Communications, can perform.
This mechanism could also prove useful for heat management applications, especially in modern electronics, where processors, power components, batteries, optical devices, and temperature-sensitive sensors are often cramped into compact spaces.
Now, thermal cloaking itself is not new. Researchers have previously demonstrated flat, or effectively two-dimensional thermal cloaks, bilayer devices, and even an ultrathin “stealth sheet” that can hide and fake heat signatures. However, most earlier experimental devices worked with circular, spherical, or extruded shapes, or performed properly only when heat arrived along a prescribed axis.
