Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Lehigh group reports best threshold values for near-infrared range InGaAsN lasers

16.12.2003


The ink was hardly dry on his new contract as assistant professor of electrical and computer engineering at Lehigh, when Nelson Tansu announced a breakthrough in his research into high-performance lasers.




In two recent issues of Applied Physics Letters (APL) - on July 7 and Sept. 29, Tansu and other collaborating researchers reported the best threshold values to date for near-infrared-range (with an emission wavelength of 1300-nm), indium-gallium-arsenide-nitride (InGaAsN) lasers emitting from a quantum well.

Tansu’s group also achieved the best threshold values yet for near-infrared-range quantum-well (QW) lasers operating under continuous-wave conditions at temperatures up to 100 degrees C.


The work of Tansu’s group was featured in the September issue of LaserFocusWorld, a photonics and optoelectronics industry journal.

One month later, on Oct. 10, Tansu was featured in the cover article of GATRA, the second-most widely circulated weekly news magazine in Indonesia (population 250 million), where Tansu was born and raised. The article described five Indonesians who are employed as university professors outside Indonesia.

The first APL article, titled "High-performance and high-temperature continuous-wave-operation 1300-nm InGaAsN quantum well lasers by organometallic vapor phase epitaxy," is one of eleven journal and conference papers Tansu has published since joining the Lehigh faculty.

The other articles have appeared in several APLs, IEEE’s Journal of Quantum Electronics, IEEE’s Journal of Selected Topics in Quantum Electronics, the Proceedings of the 16th IEEE Laser and Electro Optics Society Annual Meeting (2003), and other journals and conference proceedings. Tansu has also been invited to write a review paper on the physics and devices of dilute nitride lasers for an issue of the IOP’s Journal of Physics: Condensed Matter Physics in 2004.

The general goal of Tansu’s work is to use metal organic chemical vapor deposition (MOCVD) to develop lasers and advanced compound semiconductor nanostructures for optoelectronic devices. His research interests are also related to combining these semiconductor nanostructures with photonic crystals (artificial structures with periodicity of certain optical properties), to realize novel optoelectronic devices. His work has applications in optical communications, mid-infrared devices, free-space communications, visible light sources, information sciences, and biochemical detection.

Tansu says the criteria for high-performance lasers include low operating current, high efficiency, the ability to operate at high speeds at a range of temperatures (from room temperature to 100 degrees C.), and the ability to operate at high temperatures without the need for costly additional electronics to maintain thermal stability.

One type of laser with which Tansu works is high-performance VCSELs, or vertical cavity surface-emitting lasers, which are cheap to produce and operate at a low current. VCSELs are used in short-haul communications systems, which operate with an 850-nm wavelength, allow a transmission range of about 200-500 meters and are typically used in university campuses, offices, residential complexes, and similar venues.

The accomplishments by Tansu’s group have the potential to lead to the realization of low-cost and high-performance 1300-nm VCSELs, capable of a transmission rate of 10 gigabytes per second. Tansu’s group is one of the first to realize high-performance near-infrared range InGaAsN quantum wells by using MOCVD technology, which is the technology of choice to realize VCSELs in manufacturing. Near-infrared range lasers, which operate with a 1300-nm wavelength, allow a transmission range of 20 to 100 kilometers and are also called metropolitan optical networks because they can connect cities that are in close proximity.

The group achieved its breakthrough using InGaAsN, a new lasing material also known as dilute-nitride, on a gallium-arsenide substrate, instead of the conventional approach based on indium-phosphide technology.

"Using dilute-nitride grown on a gallium-arsenide base," says Tansu, "it is much easier to make the high-performance reflectors that are critical to achieving high-performance VCSELs. We accomplished this by using MOCVD, which is also known as MOVPE [Metal-Organic Vapor Phase Epitaxy]."

Tansu’s works represent the first realization of MOCVD-grown high-performance 1300-nm dilute-nitride lasers under continuous-wave (CW) operations rather than pulsed conditions, and with a better performance than that achieved with molecular beam epitaxy. (A German research group previously demonstrated that type of high-performance laser with molecular beam epitaxy.) CW is a virtual prerequisite for lasers to be used in real-world applications; pulsed conditions are typically used in the early stages of experimentation.

The lasers in Tansu’s system emit from a 6-nm-thick quantum well that is grown on a dilute-nitride semiconductor nanostructure layer using a strained-compensated technique.

Tansu earned his bachelor’s and Ph.D. degrees in 1998 and 2003, respectively, from the University of Wisconsin-Madison, where he also won the 2003 Harold A. Peterson Best Research Paper Award.


Kurt Pfitzer | Lehigh University
Further information:
http://www3.lehigh.edu/engineering/news/tansuvaluesforinfraredrange.asp

More articles from Physics and Astronomy:

nachricht Tiniest Particles Shrink Before Exploding When Hit With SLAC's X-ray Laser
05.02.2016 | Tohoku University

nachricht Scientists create new state of matter: Quantum gas, liquid and crystal all-in-one
02.02.2016 | Universität Stuttgart

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: Automated driving: Steering without limits

OmniSteer project to increase automobiles’ urban maneuverability begins with a € 3.4 million budget

Automobiles increase the mobility of their users. However, their maneuverability is pushed to the limit by cramped inner city conditions. Those who need to...

Im Focus: Microscopy: Nine at one blow

Advance in biomedical imaging: The University of Würzburg's Biocenter has enhanced fluorescence microscopy to label and visualise up to nine different cell structures simultaneously.

Fluorescence microscopy allows researchers to visualise biomolecules in cells. They label the molecules using fluorescent probes, excite them with light and...

Im Focus: NASA's ICESat-2 equipped with unique 3-D manufactured part

NASA's follow-on to the successful ICESat mission will employ a never-before-flown technique for determining the topography of ice sheets and the thickness of sea ice, but that won't be the only first for this mission.

Slated for launch in 2018, NASA's Ice, Cloud and land Elevation Satellite-2 (ICESat-2) also will carry a 3-D printed part made of polyetherketoneketone (PEKK),...

Im Focus: Sinking islands: Does the rise of sea level endanger the Takuu Atoll in the Pacific?

In the last decades, sea level has been rising continuously – about 3.3 mm per year. For reef islands such as the Maldives or the Marshall Islands a sinister picture is being painted evoking the demise of the island states and their cultures. Are the effects of sea-level rise already noticeable on reef islands? Scientists from the ZMT have now answered this question for the Takuu Atoll, a group of Pacific islands, located northeast of Papua New Guinea.

In the last decades, sea level has been rising continuously – about 3.3 mm per year. For reef islands such as the Maldives or the Marshall Islands a sinister...

Im Focus: Energy-saving minicomputers for the ‘Internet of Things’

The ‘Internet of Things’ is growing rapidly. Mobile phones, washing machines and the milk bottle in the fridge: the idea is that minicomputers connected to these will be able to process information, receive and send data. This requires electrical power. Transistors that are capable of switching information with a single electron use far less power than field effect transistors that are commonly used in computers. However, these innovative electronic switches do not yet work at room temperature. Scientists working on the new EU research project ‘Ions4Set’ intend to change this. The program will be launched on February 1. It is coordinated by the Helmholtz-Zentrum Dresden-Rossendorf (HZDR).

“Billions of tiny computers will in future communicate with each other via the Internet or locally. Yet power consumption currently remains a great obstacle”,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AKL’16: Experience Laser Technology Live in Europe´s Largest Laser Application Center!

02.02.2016 | Event News

From intelligent knee braces to anti-theft backpacks

26.01.2016 | Event News

DATE 2016 Highlighting Automotive and Secure Systems

26.01.2016 | Event News

 
Latest News

A new potential biomarker for cancer imaging

05.02.2016 | Life Sciences

Graphene is strong, but is it tough?

05.02.2016 | Materials Sciences

Tiniest Particles Shrink Before Exploding When Hit With SLAC's X-ray Laser

05.02.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>