Illustration of Devices (image) Harvard University Caption Two different coupling devices based on the herringbone pattern have been created: a rectangular array and a ring-shaped array (both interpreted in this illustration). Circularly polarized light with waves that wind in opposite directions gets split by both devices, with its waves routed in opposite directions. For a ring-shaped coupler, this means that plasmons are channeled either toward or away from the center of the structure. Intensity at the center of the ring can therefore be switched on and off by manipulating the polarization of the incoming light. Credit Image courtesy of Jiao Lin and Samuel Twist. Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.