Dual-polarization strong nonreciprocal radiation by the 2D GaAs nanograting

Nonreciprocity has become a research hotspot in the field of thermal radiation. Nonetheless, the majority of current nonreciprocal thermal radiation is confined to TM polarization. This paper introduces a two-dimensional nanograting structure exhibiting strong dual-polarization nonreciprocal thermal radiation. The grating is composed of a GaAs-based periodic nanoarray, a magneto-optic medium layer (InAs), and a metallic reflective layer (Al). The impact of nonreciprocity under different polarizations was investigated using rigorous coupled-wave analysis. Additionally, the magnetic field energy distribution was studied, and an explanation for the observed phenomenon of the device's nonreciprocal thermal radiation was given for both TE and TM polarizations. The present study is expected to contribute insights for the study of nonreciprocal thermal radiation.