Nonreciprocal absorber with a narrow band of angular polarization sensitive regions based on a quasi-periodic structure.

In the quasi-periodic structure (QPS) containing InSb, a nonreciprocal absorber with a narrow band of angular polarization sensitive regions is studied. Due to the effective role of the antireflection layers (ALs), the effective impedance of the overall structure matches the vacuum wave impedance. Benefiting from the special absorption structure, an absorption band will be created in the photonic bandgap. The results of the investigation show that, with the same parameters, the QPS has a larger frequency bandwidth than the periodic structure and, if the incident frequency of the electromagnetic wave is the same, the former has a larger angular selective range. The degrees of polarization separation and nonreciprocal ability of the presented QPS can be regulated by temperature and magnetic induction intensity. Consequently, the proposed QPS can provide a new basis for the development of polarization separators and nonreciprocal devices.