In less than 30
femtosecond (30 quadrillionths of a second), high energy hot electrons
in graphene bounce
off one another as they cool and spread apart. A recently
developed
technique allows researchers to access and control this cooling process.
IMAGE CREDIT:
IMAGE: ELLA MARUSHCHENKO (ELLA MARU STUDIO)
(January 19, 2016) Technique
developed by researchers could have applications in visual displays, solar
cells and photodetectors
Two University of California, Riverside assistant professors
of physics are among a team of researchers that have developed a new way of
seeing electrons cool off in an extremely short time period.
The development could have applications in numerous places
where heat management is important, including visual displays, next-generation
solar cells and photodetectors for optical communications.
An illustration
showing single layers of graphene with thin layers of insulating
boron nitride that
form a sandwich structure.
ILLUSTRATION
CREDIT: QIONG MA
In visual displays, such as those used in cell phones and
computer monitors, and photodetectors, which have a wide variety of
applications including solar energy harvesting and fiber optic
telecommunications, much of the energy of the electrons is wasted by heating
the material. Controlling the flow of heat in the electrons, rather than wasting
this energy by heating the material, could potentially increase the efficiency
of such devices by converting excess energy into useful power.