Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

World's first microlaser emitting in 3-D

09.12.2010
Scientists in Slovenia describe practical, tunable, 3-D microdroplet laser in Optics Express

Versatile electronic gadgets should employ a number of important criteria: small in size, quick in operation, inexpensive to fabricate, and deliver high precision output. A new microlaser, developed at the Jožef Stefan Institute in Ljubljana, Slovenia embodies all these qualities. It is small, tunable, cheap, and is essentially the world's first practical three-dimensional laser.

As described in Optics Express, an open-access journal published by the Optical Society (OSA), Slovenian scientists Matjaž Humar and Igor Muševiè have developed a microdroplet 3-D laser system in which laser light shines forth in all directions from dye molecules lodged within spherical drops of helical molecules dispersed in a liquid solution.

This is the first practical 3-D laser ever produced," says Muševiè, who expects that the microdroplet lasers, which can be made by the millions in seconds, will be used in making arrays of coherent light emitters. These will be handy for a variety of imaging purposes, for example "internal-source holography." Here a 3-D laser would be embedded inside the object which is to be imaged; light coming directly from the source interferes with the light scattered by the surroundings. A three-dimensional image of the object can then be reconstructed from the interference pattern.

The helical molecules are cholesteric liquid crystals, related to the molecules that form the backbone of liquid crystal displays. The cholesteric molecules don't mix well with the surrounding polymer liquid. This incompatibility sets up a curious condition: the index of refraction of the cholesteric liquid crystal varies periodically outwards through the body of the 15-micron-sized droplet. It's as if the droplet were an onion with the layers corresponding to materials with a different index of refraction.

Most lasers possess two important ingredients: an active medium in which energy can be turned into light and amplified, and some resonant enclosure in which the developing coherent light can build up to a potent beam emerging as laser light. In the case of the microdroplet laser, the active medium consists of all those fluorescent dye molecules nestled in the liquid crystals. And the resonant enclosure consists not of the usual longitudinal shaped mirrored cavity, but of the nested sequence of "onion-layer" regions of changing index of refraction.

Two more features make this laser design highly workable. First, the laser components are self-assembled. Instead of an expensive fabrication process, the parts of the laser assemble spontaneously through chemistry. Second, the laser can be tuned: by changing the pitch size of the helical molecules --the degree of their corkscrew thread-- the wavelength of the light can be altered.

"Scientists have been trying to make these lasers from solid state materials, but you can imagine how difficult it is to make hundreds of alternating shells of optical materials, which should be very uniform," said Muševiè. "The beauty of our approach is that such a 3-D onion droplet is self-assembled in a fraction of a second."

To tune the laser you don't even have to replace the droplets. Their optical properties can be changed by modifying the temperature. Tuning might even be accomplished by applying an extra electric field to the drops.

Last year, an early version of the 3-D laser resonator was reported. Now in the journal Optics Express, the fully tunable version of the laser is described.

The paper "3D microlasers from self-assembled cholesteric liquid-crystal microdroplets" by Matjaž Humar and Igor Muševiè appears in the journal Optics Express. It can be accessed at: http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-18-26-26995

The authors' lab website is located at http://www.softmatter.si.

About Optics Express

Optics Express reports on new developments in all fields of optical science and technology every two weeks. The journal provides rapid publication of original, peer-reviewed papers. It is published by the Optical Society and edited by C. Martijn de Sterke of the University of Sydney. Optics Express is an open-access journal and is available at no cost to readers online at http://www.OpticsInfoBase.org/OE.

About OSA

Uniting more than 106,000 professionals from 134 countries, the Optical Society (OSA) brings together the global optics community through its programs and initiatives. Since 1916 OSA has worked to advance the common interests of the field, providing educational resources to the scientists, engineers and business leaders who work in the field by promoting the science of light and the advanced technologies made possible by optics and photonics. OSA publications, events, technical groups and programs foster optics knowledge and scientific collaboration among all those with an interest in optics and photonics. For more information, visit www.osa.org.

Lyndsay Basista | EurekAlert!
Further information:
http://www.osa.org

More articles from Physics and Astronomy:

nachricht X-ray photoelectron spectroscopy under real ambient pressure conditions
28.06.2017 | National Institutes of Natural Sciences

nachricht New photoacoustic technique detects gases at parts-per-quadrillion level
28.06.2017 | Brown University

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>