Photosynthesis-Like Optical Energy Transfer System Developed
29 May 2014
A new, non-radiative energy transfer method that mimics the process of photosynthesis by trapping light in an optical cavity was recently detailed in the Nature Materials journal.
Scientists from the University of Southampton, in collaboration with colleagues from Sheffield and Crete, have developed an alternative to conventional Forster Resonance Energy Transfer (FRET) methods that are limited to working only in distances of 1 to 10 nanometers. By exploiting the properties of light trapped in an optical cavity, the new method allows transfers over longer distances because light there exists in a quantum state between matter and light.
The cavity is made of two metallic mirrors that capture photons in a confined space together with two types of organic molecules. The trapped photons interact with the excited states of these molecules, resulting in a combined new quantum state that glues together the mechanical states in the molecules. Thus a new half-matter, half-light particle is created - a polariton. This is what allows the efficient transfer of energy between different materials.
According to Dr Niccolo Somaschi from the University of Southampton's Hybrid Photonics group, co-author of the study, the technology brings new understanding of the process of photosynthesis and researchers are closer than ever to replicating it in fully synthetic systems. What the new method suggests, he says, is that the natural process plants use to transfer energy is directly linked with coherent coupling of molecules.
Possible applications of the technology could be found in different areas where the ability to control the formation and transport of carriers in molecular systems is key to good performance. This includes optoelectronic devices, photovoltaics and light-emitting systems.