Development of GeSn Waveguide Lasers for SWIR and MWIR Applications
Abstract
Infrared lasers in the short wavelength (SWIR) and mid wavelength (MWIR) are necessary for avariety of military applications including high-speed communications, targeting and acquisitionfor air-based munitions, and spectroscopy for explosives detection. The lasers currently used aretypically fabricated from III-V materials (e.g. InGaAs), which are expensive to produce and arenot compatible with CMOS processing protocols used for low-cost, high-volume production insilicon. In recent years, Sn-based Group IV alloys have shown promise for SWIR and MWIRapplications. These materials can be grown on Si substrates, can be doped to be either n-type or ptype, and have been identified as a possible gain medium for infrared lasing. More recently, stimulated emission has been demonstrated in optically-pumped GeSn waveguidesoperating at room temperature and at cryogenic temperatures. With this project, we aim to developa pathway to electrically-pumped lasers made from GeSn materials, i.e. GeSn laser diodes. First,we plan to build upon the initial waveguide work where optical pumping was used. The cavitydesign and fabrication process will be optimized for layers with Sn contents ranging from 6-12%.This will involve using both computational and experimental work, and will include changingwaveguide dimensions for optimal modes, modifying etching and lithography processes toproduce smooth sidewalls to reduce loss, and implementation of multilayer dielectric coatings forhigh reflectors and output couplers. Once the waveguides have been optimized, we will modifythe design to include doped layers to form p-n junctions and metal electrodes to enable electricalinjection, produce prototype laser diodes, and measure the laser emission.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 02, 2017
- Source ID
- FA95501710146
Entities
People
- Jay Mathews
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Dayton