A third group of researchers, at the Chinese University of Hong Kong in Shatin, created a graphenephotodetector that could detect longer wavelength of light, in the mid-infrared part of the spectrum.

15 September 2013- Source: http://www.nature.com/news/graphene-makes-light-work-of-optical-signals-1.13744

Image Source: http://images.iop.org/objects/phw/news/14/3/30/belle1.jpg