Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Ultrafast technique unlocks design principles of quantum biology

University of Chicago researchers have created a synthetic compound that mimics the complex quantum dynamics observed in photosynthesis. The compound may enable fundamentally new routes to creative solar light harvesting technologies.

Credit: Graham Griffin
University of Chicago researchers have created a synthetic compound that mimics the complex quantum dynamics observed in photosynthesis. The compound may enable fundamentally new routes to creative solar light harvesting technologies.

Credit: Graham Griffin

Abstract:
University of Chicago researchers have created a synthetic compound that mimics the complex quantum dynamics observed in photosynthesis and may enable fundamentally new routes to creating solar-energy technologies. Engineering quantum effects into synthetic light-harvesting devices is not only possible, but also easier than anyone expected, the researchers report in the April 18 edition of Science Express.

Ultrafast technique unlocks design principles of quantum biology

Chicago, IL | Posted on April 21st, 2013

The researchers have engineered small molecules that support long-lived quantum coherences. Coherences are the macroscopically observable behavior of quantum superpositions. Superpositions are a fundamental quantum mechanical concept, exemplified by the classic Schrodinger's Cat thought experiment, in which a single quantum particle such as an electron occupies more than one state simultaneously.

Quantum effects are generally negligible in large, hot, disordered systems. Nevertheless, the recent ultrafast spectroscopy experiments in UChicago chemistry Prof. Greg Engel's laboratory have shown that quantum superpositions may play a role in the near perfect quantum efficiency of photosynthetic light harvesting, even at physiological temperatures.

Photosynthetic antennae - the proteins that organize chlorophylls and other light-absorbing molecules in plants and bacteria - support superpositions that survive for anomalously long times. Many researchers have proposed that organisms have evolved a means of protecting these superpositions. The result: improved efficiency in transferring energy from absorbed sunlight to the parts of the cell that convert solar energy to chemical energy. The newly reported results demonstrate that his particular manifestation of quantum mechanics can be engineered into man-made compounds.

The researchers modified fluorescein - the same molecule once used to dye the Chicago River green for St. Patrick's Day - and then linked different pairs of these dyes together using a rigid bridging structure. The resulting molecules were able to recreate the important properties of chlorophyll molecules in photosynthetic systems that cause coherences to persist for tens of femtoseconds at room temperature.

"That may not sound like a very long time - a femtosecond is a millionth of a billionth of a second," said study co-author Dugan Hayes, a UChicago graduate student in chemistry. "But the movement of excitations through these systems also occurs on this ultrafast timescale, meaning that these quantum superpositions can play an important role in energy transfer."

To detect evidence of long-lived superpositions, the researchers created a movie of energy flow in the molecules using highly engineered laboratories and state-of-the-art femtosecond laser systems. Three precisely controlled laser pulses are directed into the sample, causing it to emit an optical signal that is captured and directed into a camera.

By scanning the time delays between the arriving laser pulses, the researchers create a movie of energy flow in the system, encoded as a series two-dimensional spectra. Each two-dimensional spectrum is a single frame of the movie, and contains information about where energy resides in the system and what pathways it has followed to get there.

These movies show relaxation from high energy states toward lower energy states as time proceeds, as well as oscillating signals in very specific regions of the signal, or quantum beats. "Quantum beats are the signature of quantum coherence, arising from the interference between the different energetic states in the superposition, similar to the beating heard when two instruments that are slightly out of tune with each other try to play the same note," Hayes explained.

Computer simulations have shown that quantum coherences work in photosynthetic antennae to prevent excitations from getting trapped on their way to the reaction center, where the conversion to chemical energy begins. In one interpretation, as the excitation moves through the antenna, it remains in a superposition of all possible paths at once, making it inevitable that it proceeds down the proper path. "Until these coherences were observed in synthetic systems, it remained dubious that such a complex phenomenon could be recreated outside of nature," Hayes said.

####

For more information, please click here

Contacts:
Steve Koppes

773-702-8366

Copyright © University of Chicago

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Iranian Scientists Produce Reusable Nanoadsorbent to Detect Sulfamide in Chicken July 27th, 2014

Breakthrough laser experiment reveals liquid-like motion of atoms in an ultra-cold cluster: University of Leicester research team unlocks insights into creation of new nano-materials July 25th, 2014

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Discoveries

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Iranian Scientists Produce Reusable Nanoadsorbent to Detect Sulfamide in Chicken July 27th, 2014

New imaging agent provides better picture of the gut July 25th, 2014

Breakthrough laser experiment reveals liquid-like motion of atoms in an ultra-cold cluster: University of Leicester research team unlocks insights into creation of new nano-materials July 25th, 2014

Announcements

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Iranian Scientists Produce Reusable Nanoadsorbent to Detect Sulfamide in Chicken July 27th, 2014

Breakthrough laser experiment reveals liquid-like motion of atoms in an ultra-cold cluster: University of Leicester research team unlocks insights into creation of new nano-materials July 25th, 2014

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Energy

Oregon chemists eye improved thin films with metal substitution: Solution-based inorganic process could drive more efficient electronics and solar devices July 21st, 2014

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2014 conference July 8th, 2014

Nanobiotechnology

Scientists Test Nanoparticle "Alarm Clock" to Awaken Immune Systems Put to Sleep by Cancer July 25th, 2014

Production of Non-Virus Nanocarriers with Highest Amount of Gene Delivery July 17th, 2014

Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen and not deadly carbon monoxide preferably binds to the proteins that transport it around the body. July 17th, 2014

Tiny DNA pyramids enter bacteria easily -- and deliver a deadly payload July 9th, 2014

Solar/Photovoltaic

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

Making dreams come true: Making graphene from plastic? July 2nd, 2014

Shrinky Dinks close the gap for nanowires July 1st, 2014

New Study Raises Possibility of Production of P-Type Solar Cells July 1st, 2014

Quantum nanoscience

Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen and not deadly carbon monoxide preferably binds to the proteins that transport it around the body. July 17th, 2014

Bending the rules: A UCSB postdoctoral scholar in physics discovers a counterintuitive phenomenon: the coexistence of superconductivity with dissipation June 29th, 2014

Singapore Researchers Use FEI Titan S/TEM to Link Plasmonics with Molecular Electronics: As described in the March 28 issue of Science, researchers discover quantum plasmonic tunneling a phenomenon that may eventually lead to new, ultra-fast electrical circuits June 24th, 2014

New quantum mechanism to trigger the emission of tunable light at terahertz frequencies June 18th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE