In this Letter,we propose a metagrating consisting of simple rectangular bars for nearly unity anomalous diffraction with a large deflection angle.The analysis performed by the scattering-matrix method shows that such...In this Letter,we propose a metagrating consisting of simple rectangular bars for nearly unity anomalous diffraction with a large deflection angle.The analysis performed by the scattering-matrix method shows that such exceptional beam steering derives from the couplings of the two lowest propagation waveguide-array-modes and their constructive interferences.The tolerance of the incident angle for a high diffraction efficiency(e.g.,>90%)is within a range of 33°.We also discuss that such an advantage still exists after considering a reasonable loss and dispersion.We envision that the proposed strategy may have wide use in the field of high-performance wavefront-shaping applications.展开更多
基金supported by the State Key Research and Development Program of China(No.2019YFB2203502)the National Natural Science Foundation of China(Nos.11761161002 and 61775243)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(No.2018B030308005)the Science and Technology Program of Guangzhou(No.201804020029)
文摘In this Letter,we propose a metagrating consisting of simple rectangular bars for nearly unity anomalous diffraction with a large deflection angle.The analysis performed by the scattering-matrix method shows that such exceptional beam steering derives from the couplings of the two lowest propagation waveguide-array-modes and their constructive interferences.The tolerance of the incident angle for a high diffraction efficiency(e.g.,>90%)is within a range of 33°.We also discuss that such an advantage still exists after considering a reasonable loss and dispersion.We envision that the proposed strategy may have wide use in the field of high-performance wavefront-shaping applications.
