University of California, San Diego (UCSD) researcher Zhaowei Liu and colleagues have taken the first steps in developing high-modulation-rate blue and green LEDs for underwater optical communications. They have created a nanostructured metamaterial with silver (Ag) and silicon (Si) that boosts the spontaneous-emission rate rate of a fluorescent light-emitting dye molecule—Rhodamine 6G (R6G)—by a factor of 76, as well as increasing the emission intensity of the dye by a factor of 80.1
The nanopatterned hyperbolic metamaterial (HMM) causes normally nonradiative plasmonic modes to radiate outward as light, resulting in the very large spontaneous-emission rate. In theory, the HMM used can be tuned to any wavelength in the visible spectrum for use with other dyes by altering the ratio of Ag to Si in the metamaterial.
No comments: