Metamaterial Breaks Thermal Symmetry, Enables One-Way Heat Emission

Scientists have created a groundbreaking metamaterial that breaks Kirchhoff’s law by emitting 43% more mid-infrared radiation in one direction than it absorbs. Built from layered InGaAs and tested at 512°F with a 5T magnetic field, the structure exhibits record thermal nonreciprocity. This breakthrough enables controlled one-way heat flow, a step toward thermal diodes and transistors. Unlike previous weak and narrowband effects, this design works across multiple angles and wavelengths. The discovery has major implications for heat management, solar thermophotovoltaics, and energy harvesting technologies.