%0 Journal Article %J NANO LETTERS %D 2014 %T Electrically Tunable Metasurface Perfect Absorbers for Ultrathin Mid-Infrared Optical Modulators %A Yao, Yu %A Shankar, Raji %A Mikhail A. Kats %A Song, Yi %A Kong, Jing %A Loncar, Marko %A Federico Capasso %K electrically tunale %K graphene %K Metasurface perfect absorbers %K mid-infrared optoelectonics %K optical modulators %X 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 particular, we demonstrated ultrathin (thickness < lambda(0)/10) high speed (up to 20 GHz) optical modulators over a broad wavelength range (5-7 mu m). The operating wavelength can be scaled from the near-infrared to the terahertz by simply tailoring the metasurface and cavity dimensions. %B NANO LETTERS %I AMER CHEMICAL SOC %C 1155 16TH ST, NW, WASHINGTON, DC 20036 USA %V 14 %P 6526-6532 %8 NOV %G eng %U https://doi.org/10.1021/nl503104n %N 11 %9 Article %R 10.1021/nl503104n