Electrically Tunable Metasurface Perfect Absorbers for Ultrathin Mid-Infrared Optical Modulators

Dynamically reconfigurable metasurfaces open up unprecedented opportunities in applications such as high capacity communications, dynamic beam shaping, hyperspectral imaging, and adaptive optics. The realization of high performance metasurface-based devices remains a great challenge due to very limited tuning ranges and modulation depths. Here we show that a widely tunable metasurface composed of optical antennas on graphene can be incorporated into a subwavelength-thick optical cavity to create an electrically tunable perfect absorber. By switching the absorber in and out of the critical coupling condition via the gate voltage applied on graphene, a modulation depth of up to 100% can be achieved. In…

• NS
  National Science Foundation

  Award: EECS-1028519
• IA
  Intelligence Advanced Research Projects Activity

  Award: N66001-13-1-2007 vice N66001-13-1-3005
• AF
  Air Force Office of Scientific Research

  Award: FA9550-12-1-0289