Guided Bloch surface wave resonance for multispectral enhancement of absorption in mono-layer grapheme

• Published in: Optik (Stuttgart) 2021-04, Vol.231, p.166460, Article 166460
• Main Authors: Wang, Shengyao, Zheng, Gaige, Xian, Fenglin, Xu, Dongdong, Hua, Xiaomin
• Format: Article
• Language: English
• Subjects: Bloch surface wave; Distributed Bragg reflector; Graphene; Multispectral absorber
• ISSN: 0030-4026; 1618-1336
• DOI: 10.1016/j.ijleo.2021.166460

A multispectral absorber based on Bloch surface wave (BSW) resonance with distributed Bragg reflectors (DBRs) coated with monolayer graphene is proposed. The guided Bloch surface wave resonance (GBSWR) is realized by coupling the diffraction of a subwavelength grating with the BSW at the interface between a 1D-PhC and graphene layer. Strong absorption phenomenon occurs induced by the coupling of the incident light and GBSWR. The highly efficient absorption and spectral selectivity with designing structural parameters in the visible range are verified through the rigorous coupled-wave analysis (RCWA) method. It is found that the number of absorption peaks is strongly related with the stacked period number of two dielectric materials in DBR. Compared with previous studies, not only the complete absorption of single-atomic-layer graphene can be achieved, but also the above 90 % absorption for all of resonance positions is maintained. These characteristics open up new methods of enhancing the light-graphene interaction, which may find potential application in high-performance modulators and sensors.