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

November 1, 2017
  |
Journal Article
Author:
Christine A. Wang
…
Published in:
IEEE J. Sel. Top. Quantum Electron., Vol. 23, No. 6, November/December 2017, 1200413.
Topic:
lasers
R&D area:
R&D group:

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.
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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...

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

Coherent beam-combining of quantum cascade amplifier arrays

May 10, 2015
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Conference Paper
Author:
Brian G. Saar
…
Published in:
CLEO: Conf. on Lasers and Electro-Optics, 10-15 May 2015.
Topic:
lasers
R&D area:
R&D group:

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.
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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.

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Coherent beam-combining of quantum cascade amplifier arrays

Active hyperspectral imaging using a quantum cascade laser (QCL) array and digital-pixel focal plane array (DFPA) camera

June 16, 2014
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Journal Article
Author:
Anish K. Goyal
…
Published in:
Opt. Express, Vol. 22, No. 12, 16 June 2014, pp. 14392-14401.
Topic:
lasers
R&D area:
R&D group:

Summary

We demonstrate active hyperspectral imaging using a quantum-cascade laser (QCL) array as the illumination source and a digital-pixel focal-plane-array (DFPA) camera as the receiver. The multi-wavelength QCL array used in this work comprises 15 individually addressable QCLs in which the beams from all lasers are spatially overlapped using wavelength beam combining (WBC). The DFPA camera was configured to integrate the laser light relfected from the sample and to perform on-chip subtraction of the passive thermal background. A 27-frame hyperspectral image was acquired of a liquid contaminant on a diffuse gold surface at a range of 5 meters. The measured spectral reflectance closely matches the calculated reflectance. Furthermore, the high-speed capabilities of the system were demonstrated by capturing differential reflectance images of sand and KClO3 particles that were moving at speeds of up to 10 m/s.
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Summary

We demonstrate active hyperspectral imaging using a quantum-cascade laser (QCL) array as the illumination source and a digital-pixel focal-plane-array (DFPA) camera as the receiver. The multi-wavelength QCL array used in this work comprises 15 individually addressable QCLs in which the beams from all lasers are spatially overlapped using wavelength beam...

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Active hyperspectral imaging using a quantum cascade laser (QCL) array and digital-pixel focal plane array (DFPA) camera

Single-mode tapered quantum cascade lasers

May 6, 2013
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Journal Article
Author:
Patrick Rauter
…
Published in:
Appl. Phys. Lett., Vol. 102, No. 18, 6 May 2013.
Topic:
lasers
R&D area:
R&D group:

Summary

We demonstrate tapered quantum cascade lasers monolithically integrated with a distributed Bragg reflector acting as both a wavelength-selective back mirror and a transverse mode filter. Each of the 14 devices operates at a different wavelength between 9.2 and 9.7 um, where nine devices feature single-mode operation at peak powers between 0.3 and 1.6W at room temperature. High output power and excellent beam quality with peak brightness values up to 1.6MW cm^-2 sr^-1 render these two-terminal devices highly suitable for stand-off spectroscopy applications.
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Summary

We demonstrate tapered quantum cascade lasers monolithically integrated with a distributed Bragg reflector acting as both a wavelength-selective back mirror and a transverse mode filter. Each of the 14 devices operates at a different wavelength between 9.2 and 9.7 um, where nine devices feature single-mode operation at peak powers between...

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Single-mode tapered quantum cascade lasers

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

May 1, 2013
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Conference Paper
Author:
Christine A. Wang
…
Published in:
J. Cryst. Growth, Vol. 370, May 2013, pp. 212-16.
Topic:
lasers
R&D area:
R&D group:

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.
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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...

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

High-power arrays of quantum cascade laser master-oscillator power-amplifiers

February 25, 2013
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Journal Article
Author:
Patrick Rauter
…
Published in:
Opt. Express, Vol. 21, No. 4, 25 February 2013, pp. 4518-4530.
Topic:
lasers
R&D area:
R&D group:

Summary

We report on multi-wavelength arrays of master-oscillator power-amplifier quantum cascade lasers operating at wavelengths between 9.2 and 9.8 um. All elements of the high-performance array feature longitudinal (spectral) as well as transverse single-mode emission at peak powers between 2.7 and 10 W at room temperature. The performance of two arrays that are based on different seed-section designs is thoroughly studied and compared. High output power and excellent beam quality render the arrays highly suitable for stand-off spectroscopy applications.
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Summary

We report on multi-wavelength arrays of master-oscillator power-amplifier quantum cascade lasers operating at wavelengths between 9.2 and 9.8 um. All elements of the high-performance array feature longitudinal (spectral) as well as transverse single-mode emission at peak powers between 2.7 and 10 W at room temperature. The performance of two arrays...

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High-power arrays of quantum cascade laser master-oscillator power-amplifiers

Organometallic vapor phase epitaxy of relaxed InPAs/InP as multiplication layers for avalanche photodiodes

April 1, 2008
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Conference Paper
Author:
Christine A. Wang
…
Published in:
J. Cryst. Growth, Vol. 310, No. 7-9, April 2008, pp. 1583-1589 (Proc. 13th Int. Conf. on Crystal Growth, in conjunction with Int. Conf. on Vapor Growth and Epitaxy and US Biennial Workshop on Organometallic Vapor Phase Epitaxy, 12-17 August 2007).
Topic:
photonics
R&D area:

Summary

InP1-yAsy epitaxial layers grown lattice-mismatched (LMM) on InP substrates were investigated as a new materials system for multiplication layers in Geiger-mode avalanche photodiodes (GM APDs) for detection of photons in the range 1.6-2.5 mm. LMM InP1-yAsy epilayers were grown on semi-insulating (1 0 0) InP substrates misoriented 0.2 and 2 [1 1 0] by organometallic vapor phase epitaxy at a growth temperature of 580 1C. The growth scheme used for the InP1-yAsy buffer layer was optimized based on surface step structure and X-ray diffraction. It was found that step-flow growth is a minimum criterion for obtaining good material quality. A narrower XRD full-width at half-maximum values were measured for 21-miscut substrates compared to 0.21-miscut substrates. A highquality buffer was obtained by step-grading the InP1-yAsy composition in increments of y = 0.05 over a layer thickness of 0.5 mm to a final y = 0.25. The device performance of LMM GM APDs was compared to that of measured more traditional lattice-matched GaSbbased devices. At 77 K, dark count rates of LMM devices are ~50 kHz at 5V overbias, and are comparable to GaSb-based p-i-n diodes operated in Geiger mode, while reset times of 0.02 ms are approximately 3 orders of magnitude lower than GaSb-based GM APDs.
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Summary

InP1-yAsy epitaxial layers grown lattice-mismatched (LMM) on InP substrates were investigated as a new materials system for multiplication layers in Geiger-mode avalanche photodiodes (GM APDs) for detection of photons in the range 1.6-2.5 mm. LMM InP1-yAsy epilayers were grown on semi-insulating (1 0 0) InP substrates misoriented 0.2 and 2...

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Organometallic vapor phase epitaxy of relaxed InPAs/InP as multiplication layers for avalanche photodiodes

CW operation of monolithic arrays of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors

October 1, 1993
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Journal Article
Author:
Joseph P. Donnelly
…
Published in:
IEEE Photonics Technol. Lett., Vol. 5, No. 10, October 1993, pp. 1146-1149.
Topic:
lasers
R&D area:
R&D group:

Summary

A monolithic two-dimensional array of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors was mounted junction-side up on a W / Cu microchannel heatsink and evaluated under continuous-wave (CW) operating conditions. Both the facets and parabolic deflecting mirrors were etched using chlorine ion-beam-assistd etching. Threshold current densities of different sections of the array were consistently around 240 A/cm (to the second power), and measured CW differential quantum efficiencies were in the 46-48% range. CW power densities as high as 148 W/cm (to the second power) were achieved with an average temperature rise of less than 25 degrees C in this junction-side-up configuration.
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Summary

A monolithic two-dimensional array of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors was mounted junction-side up on a W / Cu microchannel heatsink and evaluated under continuous-wave (CW) operating conditions. Both the facets and parabolic deflecting mirrors were etched using chlorine ion-beam-assistd etching. Threshold current...

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CW operation of monolithic arrays of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors
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