Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NYU physicists find way to create three-dimensional quasicrystals

12.07.2005


New York University physicists have applied a ground-breaking nanotechnology method to create three-dimensional quasicrystals, highly ordered structures that, unlike conventional crystals, never repeat themselves.



Metallic quasicrystals created from exotic alloys have shown promise for storing hydrogen more efficiently than crystalline hosts. Their non-repeating structure has the potential to dramatically strengthen industrial and commercial products. The NYU quasicrystals, by contrast, are made of glass and plastic and have potentially revolutionary optical properties.

The research, authored by NYU physicists David Grier and Yael Roichman, appears in the July 11 issue of Optics Express, a journal of the Optical Society of America.


Quasicrystals, discovered in the mid-1980s, are different from crystals, whose periodic structures resemble the patterns of tiles on a bathroom floor. By contrast, quasicrystals do not have this property, called translational symmetry, but, like crystals, can be rotated into registry with themselves, a property called rotational symmetry.

Quasicrystals’ rotational symmetry gives them many of the properties of conventional crystals. These same symmetries are responsible for conventional semiconducting crystals’ ability to act as switches for electrons. However, because quasicrystals do not possess the translational symmetry of conventional crystals, they have the freedom to take a broader range of forms, opening up the potential to serve a range of functions.

The quasicrystals reported by Roichman and Grier are created from tiny glass spheres, each comparable in size to the wavelength of light, stacked precisely in mathematically defined configurations. Like the crystalline structures responsible for the irridescence of gem opals and the colors of butterfly wings, these quasicrystalline sphere packings diffract different wavelengths of light into different directions, creating a rainbow-like display. For particular structures, and particular wavelengths, however, the quasicrystals offer no path at all for light. The resulting gaps in the rainbow, known as photonic bandgaps, can be manipulated to create switches for light. For instance, when translated into structures with features comparable to the wavelength of light, these properties of quasicrystals should enable them to manipulate light in much the same way that semiconductors manipulate electrons.

This has already been achieved for two-dimensional structures by previous researchers. However, prior to the work of Roichman and Grier, scientists had not been able to branch out into three-dimensional quasicrystals--thereby reaping the full benefits of their unique properties--because of the inability to create this class of quasicrystals with the proper materials at the right size scale.

Previous attempts at addressing this challenge included the use of lithographic techniques. In a departure from this approach, Roichman, Grier, and their colleagues used a method developed by Grier’s group called holographic optical trapping. This allows scientists to manipulate objects as small as a few nanometers across and as large as several hundred micrometers. These "optical tweezers" allow scientists to organize microscopic objects into interesting and useful configurations, to dissect them, to assemble them into devices, or to chemically transform them, all with unprecedented precision. Using this method on quasicrystals, Roichman and Grier were able to organize hundreds of free-floating microspheres into densely packed structures defined by the mathematical definition of quasicrystalline order.

Grier is part of an NYU team of internationally recognized physicists in the field of soft condensed matter physics, a new inter-disciplinary field that explores how materials are organized at microscopic levels, and which studies the physical properties of malleable materials such as colloids and polymers. With Grier, Paul Chaikin, formerly of Princeton University, and David Pine, formerly of the University of California, Santa Barbara, form the core of NYU’s Center for Soft Matter Research. Yael Roichman is a postdoctoral researcher in Grier’s group.

James Devitt | EurekAlert!
Further information:
http://www.nyu.edu

More articles from Physics and Astronomy:

nachricht SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University

nachricht Molecule flash mob
19.01.2017 | Technische Universität Wien

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: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>