Burning IT

Recently, academic debate has been swirling around the existence of unusual quantum mechanical effects in the most ubiquitous of phenomena, including photosynthesis, the process by which organisms convert light into chemical energy. In particular, physicists have suggested that entanglement (the quantum interconnection of two or more objects like photons, electrons, or atoms that are separated in physical space) could be occurring in the photosynthetic complexes of plants, particularly in the pigment molecules, or chromophores. The quantum effects may explain why the structures are so efficient at converting light into energy — doing so at 95 percent or more.

In a paper in The Journal of Chemical Physics, which is published by the American Institute of Physics, these ideas are put to the test in a novel computer simulation of energy transport in a photosynthetic reaction center. Using the simulation, professor Shaul Mukamel and senior research associate Darius Abramavicius at the University of California, Irvine show that long-lived quantum coherence is an “essential ingredient for quantum information storage and manipulation,” according to Mukamel. It is possible between chromophores even at room temperature, he says, and it “can strongly affect the light-harvesting efficiency.”

If the existence of such effects can be substantiated experimentally, he says, this understanding of quantum energy transfer and charge separation pathways may help the design of solar cells that take their inspiration from nature.

How photosynthesis achieves this near instantaneous energy transfer is a long-standing mystery that may have finally been solved.

Source and published papers @ EurekAlert

Fullerenes, also known as buckminsterfullerenes or “buckyballs,” were detected about 6,500 light years from Earth in the cosmic dust of Tc 1, an object known as a planetary nebula, researchers reported in a study published online Thursday in Science Express.

Scientists had long speculated that buckyballs, made up of 60 carbon atoms joined in a cage-like sphere, existed in space and might be responsible for light being mysteriously absorbed in space, said Jan Cami, an astronomer at the University of Western Ontario in London who was the lead author of the study.

“Now that we know for sure that these fullerenes do actually exist in space … we can actually turn the question around and say … ‘How big could their influence be in terms of these absorptions?’ So that’s a much more specific question.”

A planetary nebula such as Tc 1 is the last stage in the life of a star and is generally a colourful object with a small star called a white dwarf at its centre, Cami said.

“It’s surrounded by these layers of gases that glow typically in red and green. Those gases are actually what used to be the outer layer of the star.”

Researchers trained the Spitzer Space Telescope on Tc 1, which is visible at high magnification in the constellation Ara from the Earth’s Southern Hemisphere. They measured the infrared light absorbed by molecules in its dust cloud, which are unique for each type of molecule and can serve as a chemical fingerprint to identify them.

Jeronimo Bernard-Salas, a researcher at Cornell University in Ithaca, N.Y., and at Université Paris-Sud in Orsay, France, who specializes in studying the dust of planetary nebulae, noticed that the spectrum of Tc 1 was unusual. The dust didn’t contain carbon chains or rings that are normally found near planetary nebulae.

Bernard-Salas sent the spectrum to other researchers, including Cami, who recognized the signature as almost a perfect match for the fullerenes known as C60 and C70 (named for the number of carbon atoms in each).

Read the rest of the article at CBC News CA