Frequency converter implementing an optical analogue of the cosmological redshift.
According to general relativity, the frequency of electromagnetic radiation is altered by the expansion of the universe. This effect-commonly referred to as the cosmological redshift--is of utmost importance for observations in cosmology. Here we show that this redshift can be reproduced on a much smaller scale using an optical analogue inside a dielectric metamaterial with time-dependent material parameters. To this aim, we apply the framework of transformation optics to the Robertson-Walker metric. We demonstrate theoretically how perfect redshifting or blueshifting of an electromagnetic wave can be achieved without the creation of sidebands with a device of finite length.
Ginis
Vincent
V
Department of Applied Physics and Photonics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium. vincent.ginis@vub.ac.be
Tassin
Philippe
P
Craps
Ben
B
Veretennicoff
Irina
I