Material looks cool while heating up

Substance that tricks infrared camera could pave the way for new types of camouflage

CHILLY HEAT  Even as a sample of vanadium oxide heated up (left to right), the infrared light it emitted made the sample appear to cool down. Red normally represents hot materials and blue cold.

Courtesy of M. Kats/Harvard Univ.

It’s a thermodynamic Houdini: the first material that appears to get colder as it heats up.