▎ 摘　　要

The infrared absorption spectrum due to structural vibrations in molecules has been widely used to resolve chemical identification. However, this method is limited by the weak molecule-light interaction. Graphene plasmon, having strong confinement and large field enhancement, provides a promising way to increase their interactions. Here we propose tunable hybridization-induced graphene nanostructures for sensing application. Our results reveal that when the symmetry of the graphene disk is broken by introducing a small circular defect, dual-band resonance can be excited at mid-infrared frequencies. The dual-band resonance peaks are produced by plasmon hybridization effect between two simple structures: graphene disks and circular defects. We investigate the influence of the size and position of the circular defect on the dual-band resonance peaks. We further explore the dual-band resonance peaks for sensing, and the sensitivity can reach 550 cm(-1)/RIU and the FOM can reach 20.4. Compared to the original graphene disk structure, the results show stronger resonance intensity and higher frequency sensitivity. Our findings provide a new platform for sensing, and moreover the dual-band resonance structure feature enables us to promote the development of multi-substance detection. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement