Tuesday, April 01, 2014: Researchers at the University of Buffalo in their latest research paper titled “Broadband absorption engineering of hyperbolic metafilms patterns” have proposed the use of multi-layered waveguide taper array that opens the door for newer and better possibilities in the field of thermal energy, solar power and energy conversions. The research is spearheaded by lead researcher Qiaoqiang Gan and predicts better times to come in the aforementioned fields.
The waveguide tapers are microchip components that allow chips to trap and absorb light of each frequency thereby catching a rainbow of wavelengths or broadband light. The researchers had earlier predicted that multi-layered tapers could absorb light more efficiently, only now they have successful experimental results to prove the same. During the research multi-layered taper made up of ultra-thin layer of metal, semiconductors and/or insulators was employed. The taper, named hyperbolic metamaterial has the ability to absorb light in between pairs of layers. Adjusting the geometry and thickness of the taper results in absorbing various frequencies.
The research opens up new avenues in the field of thin-film solar technology and can also be used for recycling thermal energy. Photovoltaic cells absorb less light when compared with traditional solar cells. However, the new technology could lead to absorption of both visible as well as infrared light waves. This in turn would lead to greater energy generation by photovoltaic cells.
In another news, researchers at Nanyang Technological University (NTU) have successfully developed a new solar cell material that might hold a key spot in designing inexpensive solar cells in the days to come. The material in question: Perovskite effectively converts light into electricity but can also emit light, much to the developers’ delight. In short, the material absorbs light by day and shines by the night. When NTU physicist Sum Tze Chien and researcher Xing Guichuan projected a laser beam on a sample of the Perovskite solar cell material, the material glowed brightly contradicting the fact that most solar cell materials are not expected to generate light after it is absorbed. The new material also has a wide array of other applications: making lasers, making light decorations or displays in shopping malls and offices. Further, Perovskite can be modified to emit different colours making it useful in light emitting devices like flat-screen TV’s and monitors. What sets it apart from other solar cell materials is that Perovskite is five times cheaper than the present Silicon-based solar cells.
