One-way heat transfer in deep-subwavelength thermal metaphotonics

Nonreciprocal thermal metaphotonics, by breaking Lorentz reciprocity, exceeds current theoretical efficiency limits, unlocking opportunities to energy devices and thermal management. However, radiative heat transfer in current systems is highly defect-sensitive. This sensitivity is further amplified at deep subwavelength scales by inevitable multi-source interactions, interface wrinkles, and manufacturing tolerances, making precise control of electromagnetic heat transfer increasingly challenging. Here, we demonstrate a topological one-way heat transport in a deep-subwavelength thermophotonic lattice. This one-way radiative heat flow, driven by global resonances, is strongly confined to the geometric boundaries and demonstrates exceptional robustness against imperfections and disorder, achieving significant enhancement in radiative heat transfer.