Publications

Refine Results

(Filters Applied) Clear All

MOVPE growth of LWIR AlInAs/GaInAs/InP quantum cascade lasers: impact of growth and material quality on laser performance

Summary

The quality of epitaxial layers in quantum cascade lasers (QCLs) has a primary impact on QCL performance, and establishing correlations between epitaxial growth and materials properties is of critical importance for continuing improvements. We present an overview of the growth challenges of these complex QCL structures; describe the metalorganic vapor phase epitaxy growth of AlInAs/GaInAs/InP QCL materials; discuss materials properties that impact QCL performance; and investigate various QCL structure modifications and their effects on QCL performance. We demonstrate uncoated buried-heterostructure 9.3-um QCLs with 1.32-W continuous-wave output power and maximum wall plug efficiency (WPE) of 6.8%. This WPE is more than 50% greater than previously reported WPEs for unstrained QCLs emitting at 8.9 um and only 30% below strained QCLs emitting around 9.2 um.
READ LESS

Summary

The quality of epitaxial layers in quantum cascade lasers (QCLs) has a primary impact on QCL performance, and establishing correlations between epitaxial growth and materials properties is of critical importance for continuing improvements. We present an overview of the growth challenges of these complex QCL structures; describe the metalorganic vapor...

READ MORE

Coherent beam-combining of quantum cascade amplifier arrays

Summary

We present design, packaging and coherent beam combining of quantum cascade amplifier (QCA) arrays, measurements of QCA phase noise, the drive-current-to-optical-phase transfer function, and the small signal gain for QCAs.
READ LESS

Summary

We present design, packaging and coherent beam combining of quantum cascade amplifier (QCA) arrays, measurements of QCA phase noise, the drive-current-to-optical-phase transfer function, and the small signal gain for QCAs.

READ MORE

High power (>5 W) lambda ~9.6 um tapered quantum cascade lasers grown by OMVPE

Summary

AlInAS/GaInAs superlattices (SLs) with barrier and well layers of various thicknesses were grown by organometallic vapor phase epitaxy to optimize growth of quantum cascade lasers (QCLs). High-resolution x-ray diffraction data of nominally lattice-matched SLs show a systematic shift toward more compressively strained SLs as the barrier/well layer thicknesses are decreased below about 10 nm. This shift is attributed to In surface segregation in both AlInAs and GaInAs. This shift is compensated for in the growth of ultra-thin layers in QCL structures. QCLs with tapered gain regions and emitting at 9.6 um are demonstrated with peak power as high as 5.3 W from one facet at 20 degrees C.
READ LESS

Summary

AlInAS/GaInAs superlattices (SLs) with barrier and well layers of various thicknesses were grown by organometallic vapor phase epitaxy to optimize growth of quantum cascade lasers (QCLs). High-resolution x-ray diffraction data of nominally lattice-matched SLs show a systematic shift toward more compressively strained SLs as the barrier/well layer thicknesses are decreased...

READ MORE

High efficiency coherent beam combining of semiconductor optical amplifiers

Published in:
Opt. Lett., Vol. 37, No. 23, 1 December 2012, pp. 5006-5008.

Summary

We demonstrate 40 W coherently combined output power in a single diffraction-limited beam from a one-dimensional 47-element array of angled-facet slab-coupled optical waveguide amplifiers at 1064 nm. The output from each emitter was collimated and overlapped onto a diffractive optical element combiner using a common transform lens. Phase locking was achieved via active feedback on each amplifier's drive current to maximize the power in the combined beam. The combining efficiency at all current levels was nearly constant at 87%.
READ LESS

Summary

We demonstrate 40 W coherently combined output power in a single diffraction-limited beam from a one-dimensional 47-element array of angled-facet slab-coupled optical waveguide amplifiers at 1064 nm. The output from each emitter was collimated and overlapped onto a diffractive optical element combiner using a common transform lens. Phase locking was...

READ MORE

Advanced packaging of high-power slab-coupled optical waveguide laser and amplifier arrays for coherent beam combining

Summary

Individually addressable GaAs-based 9XX-nm Slab-Coupled Optical Waveguide (SCOW) laser and amplifier arrays have been demonstrated in a modular 2-D stacked architecture. Approximately 20 W of coherently-combined power was obtained from two optically stacked amplifier modules.
READ LESS

Summary

Individually addressable GaAs-based 9XX-nm Slab-Coupled Optical Waveguide (SCOW) laser and amplifier arrays have been demonstrated in a modular 2-D stacked architecture. Approximately 20 W of coherently-combined power was obtained from two optically stacked amplifier modules.

READ MORE

Showing Results

1-5 of 5