Near-field radiative heat transfer mediated by monolayer lateral heterostructures

Monolayer lateral heterostructures, an interesting class of nanostructures, have garnered significant attention in optoelectronics and nanoelectronics due to their unique physical properties, yet their radiative heat transfer characteristics remain poorly understood. Here, we take graphene-hBN lateral heterostructures as an example to unveil the emergence of ultrastrong thermophotonic excitations in monolayer lateral architectures, yielding radiative heat transfer that approaches an order of magnitude enhancement over their conventional vertical counterparts. Through a systematic analysis of dispersion evolution and surface wave dynamics, we attribute this enhancement to a pronounced heterointerface effect between surface polaritons supported by the constituent materials. Remarkably, this enhancement mechanism proves robust across diverse material combinations, and its radiative performance is superior to that of numerous classic heterostructures and advanced metasurfaces. These findings position monolayer lateral heterostructures as a promising framework for the manipulation of thermal photonics at the nanoscale, offering fertile ground for future investigations into the roles of exciton dynamics, carrier dynamics, and interfacial quantum effects in electromagnetic energy transport.