Distributed Feedback Interband Cascade Lasers
Summary:
Maxion Technologies, Inc. (Hyattsville, MD), develops mid-infrared semiconductor lasers for wireless optical communications, chemical sensing, and infrared countermeasures.
Technology Description:
The distributed feedback interband cascade lasers developed by the company are mid-infrared lasers based on indium-arsenide, gallium antimonide, and aluminum-antimonide materials. The distributed feedback technique used by Maxion involves use of a grating structure along the entire length of the laser that feeds back only a specific, desired wavelength into the laser’s final output. The interband cascade laser design advanced by the company meanwhile involves cascading electrons to produce multiple photons as the electrons move between the energy bands, or levels, of the multilayered semiconductor structure used for the laser.
Common mid-infrared diode lasers have power efficiencies as small as 3 percent, with 97 percent of their input power wasted as heat, according to the company. The Maxion lasers, however, can operate in continuous-wave (CW) mode at 80 Kelvin with power efficiencies higher than 17 percent. The result is that a Maxion laser can operate much more efficiently than comparable lasers and, with further development, may operate at room temperature under CW conditions.
The company has demonstrated at 80 Kelvin a continuous-wave laser with power levels around 160 milliwatts. That power compares with continuous-wave lead-salt lasers that generally generate less than about 1 milliwatt of power.
In one potential application, laser communications, the signal-weakening effects of fog will remain a challenge in free-space communications. But Maxion officials believe their 3.5-micron beams offer a benefit over 10-micron beams. While 10-micron beams work better in a dense fog, in a light fog a 3.5-micron beam can propagate better than the 1.55- and 0.8-micron beams now in use and almost as well as a 10-micron beam. Free-space communications systems with 3.5-micron beams, however, would involve less signal-detector noise than systems based on 10-micron beams. Meanwhile, reducing the noise at 10 microns would require cryogenically cooled detectors, a commercially unreasonable solution for many users.
MDA Origins:
Maxion received BMDO funding to develop distributed feedback interband cascade lasers for military applications such as wireless communications systems and chemical sensing.
Spinoff Applications:
Maxion envisions its technology as valuable for “free-space” optical (wireless) communications, chemical-sensing, and infrared countermeasures. The company has agreements with two organizations that are testing its lasers in chemical-sensing applications for potential use in portable chemical sensors, according to Maxion.
Commercialization:
Maxion officials plan to continue their research and are searching for government R&D funding that will carry the company through the next few years. The company might seek venture-capital funding in 2003.
Company Profile:
Maxion was founded in April of 2000. Of the company’s five founders, four were long-time federal employees at the Army Research Laboratory in Adelphi, MD. In the 1990s, group members at the Army laboratory focused their research on antimonide materials, concentrating specifically on III-V semiconductors that involved gallium antimonide, indium arsenide, and aluminum antimonide. The group further focused its research efforts on long-wavelength detectors from the gallium-antimonide/indium-arsenide/aluminum-antimonide system. The company now employs seven people.
Contact Information:
Dr. John D. Bruno
Maxion Technologies, Inc.
6525 Belcrest Road, Suite 523
Hyattsville, MD 20782
Tel: (301) 394-5740
Fax: (301) 394-2103
email: bruno@maxion.com
web: www.maxion.com
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