Tuning resonant reflection in monolayer graphene nanosquare arrays at mid-infrared frequencies

In this work, high resonant reflection of light has been investigated in an atomic thickness resonator consisting of monolayer graphene nanosquare arrays at mid-infrared frequencies. Our numerical results show that more than 90% light reflectivity can be realized due to excitation of dipole resonance in the gap of graphene arrays in this system. Moreover, it is found the high resonant reflection is nearly independent of polarization over a wide-angle range. The resonant wavelength can be dynamically modulated by changing the geometry of the structure or adjusting the graphene chemical potential. Our findings provide new opportunities for the development of optical reflective devices, nano-antenna and highly integrated devices with atomic thickness.