Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

“Controlling light with light”: Martini and post-doctoral researcher Murawski

02.06.2004


Near-infrared laser transfers data to mid-infrared laser’s beam



“Interband transitions controlling intersubband transitions” is the technical description for what has been achieved in an optics lab in Stevens Institute of Technology’s Physics Department. Robert K. Murawski, a post-doctoral research assistant working under the direction of Professor Rainer Martini , has a simpler way to describe it: “Controlling light with light.”

Regardless of styling, the concept is not a new one, but its first demonstration in a laboratory opens new horizons in telecommunications, with implications for the secure, all-optical transmission of voice and data. Martini credits Murawski for having made the initial measurements proving that the principle is physically possible in a controlled environment.


“Basically,” explains Murawski, “we use a conventional kind of laser beam to ‘switch’ another, more advanced kind of laser beam – and it all happens in mid air.

“One laser beam is mid-infrared,” he says. “We illuminate it directly with a fiber-optic laser diode, which is near-infrared – and if that light has a message on it, then the mid-infrared will have a message on it once it passes through. You can use the fact, then, that the mid-infrared can transmit to the atmosphere to do things like free-space communications without fiber optics.”

“All current wavelength for optical communication is near-infrared, which is highly unreliable in a free-space environment,” explains Martini, a veteran of Lucent Technologies and the director of the Ultrafast Laser Spectroscopy & Communication Laboratory at Stevens. “The mid-infrared, which is generated by what is called a ‘quantum cascade laser’ or QCL, overcomes many of those limitations in traveling through free space. Plus, because it is ultra-focused, the QCL beam is a much more secure means by which to communicate than by broadcasting or other kinds of telephony.”

Another beauty of the near-infrared/QCL assembly, says Martini, is that “your switches act on two different wavelengths, and they are clearly separate and distinct. The two wavelengths can be handled and processed in independence. There’s no overlap, because we have the whole system clearly detangled.”

Martini and Murawski are quite confident that their achievement is unique.

“In the quantum cascade physics knowledge-base,” says Murawski, “there’s little if any work that’s been done like this. Interband transitions are really not talked about.”

Murawski believes that in the field of advanced quantum cascade lasers, in the physics area, Martini’s lab has developed a more complete picture of those particular dynamics “than anyone else currently working around the world.”

“Robert’s thesis,” says Martini, “is really the first complete theoretical discussion about the immense potential of modulating QCL at high speeds. His thesis sets the limits for how fast that laser can be.”

Murawski, who defended his dissertation in early May, says that the Martini lab has also figured out “how to preserve the integrity of the hardware package. You don’t want the QCL damaged or melting down while it’s in action.”

Martini is also proud that his lab houses a unique quantum cascade laser.

“It managed the fastest-recorded QCL modulation in the world. Everybody talked about it,” he says, “but we achieved it.”

Martini says that the controlling of light with light opens up a world of futuristic applications which – because they are imaginable – may at some point be possible.

“The question is,” he says, “What is happening in the laser beam when the interband transition takes place? The QCL is unique. One of the big issues is, you send current through it, and that current drops down making the laser transition. So when the first electron drops down, it tells the other electrons to go with it. So there’s a kind of ‘intelligence among the electrons.’ If we can reach in and manipulate that action, who knows what we can engineer using the properties of the laser beam?”

Established in 1870, Stevens offers baccalaureate, masters and doctoral degrees in engineering, science, computer science, management and technology management, as well as a baccalaureate in the humanities and liberal arts, and in business and technology. The university has enrollments of approximately 1,740 undergraduates and 2,600 graduate students. Additional information may be obtained from its web page at www.Stevens.edu.

Patrick Berzinski | Stevens Institute of Technology
Further information:
http://www.stevensnewsservice.com/pr/pr439.htm

More articles from Communications Media:

nachricht New Technologies for A/V Analysis and Search
13.04.2017 | Fraunhofer-Institut für Digitale Medientechnologie IDMT

nachricht On patrol in social networks
25.01.2017 | Fraunhofer-Institut für Arbeitswirtschaft und Organisation IAO

All articles from Communications Media >>>

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

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>