Researchers have designed a material that can "program" the way it releases heat, paving the way for more efficient energy systems and, potentially, devices that store information using heat instead of electricity.
The design, described in a June 25 study in the journal Laser & Photonics Reviews, sidesteps a nearly 160-year-old rule of physics linking how materials absorb and emit heat. Under ordinary conditions, a material that's good at absorbing heat from one direction is equally good at emitting heat in that direction. This rule of reciprocity, first described by physicist Gustav Kirchhoff in the 19th century, has limited engineers' ability to control incoming heat independently from and outgoing heat.
