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 New Method of Characterizing Graphene
30.05.2017 | Universität Basel

nachricht NASA's SDO sees partial eclipse in space
29.05.2017 | NASA/Goddard Space Flight Center

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: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Reptile vocalization is surprisingly flexible

30.05.2017 | Life Sciences

EU research project DEMETER strives for innovation in enzyme production technology

30.05.2017 | Power and Electrical Engineering

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>