Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Butterflies and photonic chrystals

28.01.2003


The small structures in the scanning electron microscope image of a butterfly wing scale (a) are natural photonic crystals that give the wings of some butterflies their brilliant iridescent blue colors. The structures in the second image (b) are responsible for a blue-violet iridescence. In the third image (c), the small structures are almost entirely absent, and the butterfly wing scales are a dull brown shade. New research suggests that photonic crystals keep butterfly wings cooler, as well as making them beautiful. In higher elevations where butterflies are more reliant on sunlight to keep them warm, some of the insects have evolved wing scales in which the photonic crystals have been disrupted (as in image c), improving the chances that they survive long enough to mate despite the frigid climate.
Source: L. P. Biro et al., Physical Review E, February 2003



In recent years, scientists have discovered that the iridescence of various colorful creatures, from beetles to birds to butterflies, is often due to microscopic structures known as photonic crystals. Unlike pigments, which absorb or reflect certain frequencies of light as a result of their chemical composition, the way that photonic crystals reflect light is a function of their physical structure. That is, a material containing a periodic array of holes or bumps of a certain size may reflect blue light, for example, and absorb other colors even though the crystal material itself is entirely colorless. Because a crystal array looks slightly different from different angles (unlike pigments, which are the same from any angle), photonic crystals can lead to shifting shades of iridescent color that may help some animals attract mates or establish territories.

A collaboration of researchers from Hungary and Belgium (Jean-Pol Vigneron, Universitaires Notre-Dame de la Paix, Brussels, jean-pol.vigneron@fundp.ac.be, 011+32-81 724711) may have discovered why the males in certain populations of lycaenid butterflies carry the striking, photonic crystal coloration, and males in other lycaenid populations do not. The researchers examined butterfly scales through high-resolution scanning electron microscopes (see image), and confirmed that indeed the colorful butterflies’ scales included arrays of submicron-sized holes that formed natural photonic crystals. Their closely related brethren from higher elevations did not have the hole arrays in their scales, and their wings were dull brown rather than iridescent blue. The difference, it seems, may be due to a question of survival. The researchers found that the plain brown butterfly wings warmed much more than the iridescent blue wings when each were exposed to identical illumination. The researchers believe that the butterflies at high elevations trade flashy iridescence for light-absorbing brown so that they can withstand colder temperatures, and survive long enough to mate.

If photonic crystals can have such a dramatic impact on butterfly thermal management, suggest the researchers, manmade photonic crystals may someday provide flexible thermal protection in extreme environments, possibly being incorporated into such things as space suits or desert garments. (L. P. Biro et al, Physical Review E, February 2003; text www.aip.org/physnews/select )

Phil Shewe | Bulletin of Physics News

More articles from Physics and Astronomy:

nachricht Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics

nachricht What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>