Nonreciprocal thermal radiation has many applications in energy harvesting, military camouflage, and other fields. However, in the past, most nonreciprocal devices operated under single polarization, which undoubtedly limited the development of the nonreciprocal thermal radiation. In addition, previous research has focused on single-band nonreciprocal radiation. However, there is little study on dual-band nonreciprocal thermal radiation. We investigate a dual-band nonreciprocal radiation device under dual-polarization, which is composed of a metal layer, magneto-optical layer, and silicon-based square-hole arrays in two-dimensional form. The device can achieve dual-band nonreciprocal radiation at wavelengths of 15.945 μm and 16.475 μm under TE polarization. Under TM polarization, dual-band nonreciprocal radiation can be achieved at wavelengths of 13.956 μm and 14.352 μm. And the electromagnetic field distribution can explain potential physical mechanisms. It indicates that nonreciprocal radiation can be maintained well within a certain range of structural parameters. This work can provide new directions for the study of frequency selective detectors.
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