Large-area graphene thermal emitter based on all-dielectric Fabry-Perot cavity in the near-infrared

The exceptional saturation current density and ultrafast Joule heating modulation properties of graphene present significant potential for active thermal emission regulation. However, its practical implementation in near-infrared regimes has been constrained by inherent limitations in the low emissivity (absorptivity) and atmospheric oxidation susceptibility. In this study, we propose a large-area thermal emitter through the integration of graphene with an all-dielectric Fabry-Perot cavity. This configuration not only achieves substantial enhancement of graphene's emissivity but also provides effective passivation against ambient degradation. The fabricated emitter exhibits the same absorption and emission peak at 1416 nm, with thermal emission spectroscopy revealing an estimated electron temperature approaching 580 K under 24 V biasing conditions. Furthermore, the emission wavelength could be easily controlled by tuning the thickness of the Al₂O₃ layer. These findings establish a platform for developing graphene-based electro-thermal emission devices with enhanced performance and environmental stability, paving the way for advanced applications in dynamic thermal management and infrared optoelectronics.