Crystals Find Work as Beamsplitters

Photonic crystals have been the focus of research as all-optical systems for communications and computing move toward reality. A group at Bilkent University in Ankara, Turkey, has taken the work further with the demonstration of crystal-based beamsplitters that could find application as power splitters or switches in a photonic circuit.

In the Dec. 11, 2000, issue of Applied Physics Letters, the researchers describe how their photonic crystal of spaced alumina rods split 10.6- to 12.8-GHz electromagnetic radiation into planar or coupled-cavity waveguide channels with little loss. By altering the position of defects in the crystal, they could regulate the proportion of input power directed through the channels. The approach should be effective for optical frequencies.