Photodetectors are devices that detect light by converting
optical signals into electrical current. They are widely
employed in both science and technology, for communications,
sensing and imaging.  Modern light detectors are usually made
using III-V semiconductors, such as gallium arsenide. When light
strikes these materials, each absorbed photon creates an
electron-hole pair. These pairs then separate and produce an
electrical current.  Good at absorbing light Graphene has many
unique physical and mechanical properties that make it suitable
for detecting light. One benefit is that electrons and holes
move much faster through graphene than through other materials.
Also, graphene is very good at absorbing light over a very wide
range of wavelengths, ranging from the visible to the infrared.
This is unlike III-V semiconductors, which do not work over such
a wide range.  Despite all these advantages, graphene suffers
from one serious flaw - the electrons and holes created in the
bulk of the material normally re