The Dark Side of Light: Negative Frequency Photons
24th August 2012
A team of researchers has shown that, in some sense, negative frequencies can be observed through the generation of radiation with a positive frequency. To explore this idea, they looked at very intense light fields moving through certain types of glass and glass fibers. When the light field is very intense—as is the case when a very short, intense burst of light is created—this can lead to some very cool effects. In particular, when the light is passing through a material, the light field pushes the electrons around so hard that the electrons start to push back.