Programmable heat routing could steer infrared heat flow

Physicists propose a theoretical device that uses a magnetic field to break reciprocity in a layer of indium arsenide and a phase-change GST layer to independently control and lock how heat is absorbed and emitted. This nonvolatile programming could direct heat in one direction and hold that setting without power, potentially enabling more efficient energy systems and heat-based memory, with infrared sensing as a likely first use. The concept remains paper‑based and untested for real devices.