TITLE: Quantum Cascade Laser Thermal Impedance Improvement
TECHNOLOGY AREA(S): Air
ACQUISITION PROGRAM: JSF
Joint Strike Fighter
The technology within this
topic is restricted under the International Traffic in Arms Regulation (ITAR),
22 CFR Parts 120-130, which controls the export and import of defense-related
material and services, including export of sensitive technical data, or the
Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls
dual use items. Offerors must disclose any proposed use of foreign nationals
(FNs), their country(ies) of origin, the type of visa or work permit possessed,
and the statement of work (SOW) tasks intended for accomplishment by the FN(s)
in accordance with section 3.5 of the Announcement. Offerors are advised
foreign nationals proposed to perform on this topic may be restricted due to
the technical data under US Export Control Laws.
OBJECTIVE: Develop novel
quantum cascade laser device structures to reduce the thermal impedance
significantly (i.e., by at least a factor of two).
High-performance, midwave-infrared (MWIR) (~4.5-5um) quantum cascade lasers
(QCLs) have been reported with front-facet continuous wave (CW) output powers
as high as ~ 5W from optimized facet-coated, single-element devices mounted on
diamond heatsinks [Ref 1]. A primary and yet very critical technical challenge
in deploying higher performance and reliable QCLs for Naval applications is to
address and resolve the problems of excessive heat generation within the QCL
active region. This is caused by two fundamental aspects of the QCL: low
wall-plug efficiency and very high thermal impedance. This SBIR topic is to
address the second, critical issue of QCLs’ high thermal impedance, which
remains an Achilles' heel for QCLs that adversely impacts the performance and
reliability of high power QCLs.
It has been documented [Ref 1] that QCLs’ internal device heating is an order
of magnitude larger than for conventional near-IR diode lasers, and that QCL
performance is a strong function of the active region temperature rise. High
efficiency active region designs can be employed to minimize heat generation,
but even the best state-of-the-art QCLs at present still generate about 5-10
times the heat load of near-IR interband-transition semiconductor lasers.
Hence, the extreme heating of QCLs combined with their inherently high thermal
impedance of the superlattice (SL) structures of the active regions leads to
catastrophic facet failure, most likely caused by thermally-induced shear
stress [Ref 2]. Heat flux within a QCL can exceed kW/cm2 out of the active
region in the semiconductor, and its limited intrinsic ability to dissipate
that heat limits the range of operating power and the maximum lifetimes. For
instance, at Watt-range CW output powers, the dissipated heat typically exceeds
20 W and poses severe challenges for field compatible packaging with sufficient
thermal management. Furthermore, self-heating under CW operation aggravates
active-region carrier leakage, which degrades device performance (i.e., lower
slope efficiency and increased threshold current).
The Navy seeks innovative, monolithic QCL device structures to reduce a QCL’s
effective thermal impedance in the direction vertical to the epitaxial layers
significantly (by at least a factor of two), relative to the state-of-the-art.
The device structure should also be capable of emitting at least 5W continuous
wave output at room temperature with emission wavelength at ~4.5 um and near
diffraction-limited beam quality (M2 < 1.5). Moreover,
microscopic-physics-based heat models are also needed to elucidate interfacial
contributions to thermal resistance and guide the design of reduced overall
device thermal resistance. It is anticipated that a factor of two to three
improvement in thermal resistance would allow for a dramatic decrease in
self-heating and subsequent enhanced device performance and reliability,
especially at high output powers. Successful combined development of
substantially improved QCLs’ thermal resistance in this SBIR topic and the 40%
wall-plug efficiency in another Navy program would finally realize the vision
of enabling improvement of the overall size and weight of QCL packaging and its
active cooling system, and the associated reliability by up to a factor of 10.
Successful completion of this project and the QCL efficiency program will be
the most significant landmark achievements for the QCL in the last 15 years and
will ultimately elevate the performance, size and weight, and operating
lifetimes of QCL to their theoretical limits.
PHASE I: Develop a novel QCL
device structure model through which the effective thermal impedance in the
direction vertical to the epitaxial layers could be feasibly reduced by at
least a factor of two, relative to the state-of-the-art. Demonstrate that the
device structure is feasibly capable of emitting at least 5W continuous wave
output at room temperature with emission wavelength at ~4.5 um and near
diffraction-limited beam quality (M2 < 1.5). Produce plans to develop a
prototype under Phase II.
PHASE II: Fabricate and
demonstrate a developed QCL device prototype that produces reduced thermal
impedance and ~4.5 um emission with at least 5W continuous wave output at room
temperature and near diffraction-limited beam quality (M2 < 1.5).
PHASE III DUAL USE
APPLICATIONS: Fully develop and transition high-performance QCLs with high
thermal conductance for DoD applications in the areas of Directed Infrared
countermeasures (DIRCMs), advanced chemicals sensors, and Laser Detection and
Ranging (LIDAR). The DoD has a need for advanced, compact, high-performance MWIR
QCL arrays with high thermal impedance of which the output power can readily be
scaled via beam combining for current and future generation DIRCMs, LIDARs, and
chemicals/explosives sensing. The commercial sector can also benefit from this
crucial, game-changing technology development in the areas of detection of
toxic gases, environmental monitoring, and non-invasive health monitoring and
1. Bai, Y., Bandyopadhyay,
N., Tsao, S., Slivken, S. and Razeghi, M. “Room temperature quantum cascade
lasers with 27% wall plug efficiency.” Appl. Phys. Lett. 2011, 98, 181102, doi:
2. Zhang, Q., Liu, F., Zhang,
W., Lu, Q., Wang, L., Li, L., and Wang, Z. “Thermal induced facet destructive
feature of quantum cascade lasers.” Appl. Phys. Lett. 2010, 96, 141117. https://doi.org/10.1063/1.3385159
KEYWORDS: Quantum Cascade
Lasers; Thermal Impedance; Thermal Resistance; Midwave-infrared; Wall-plug
Efficiency; Laser Array
** TOPIC NOTICE **
These Navy Topics are part of the overall DoD 2018.2 SBIR BAA. The DoD issued its 2018.2 BAA SBIR pre-release on April 20, 2018, which opens to receive proposals on May 22, 2018, and closes June 20, 2018 at 8:00 PM ET.
Between April 20, 2018 and May 21, 2018 you may talk directly with the Topic Authors (TPOC) to ask technical questions about the topics. During these dates, their contact information is listed above. For reasons of competitive fairness, direct communication between proposers and topic authors is not allowed starting May 22, 2018 when DoD begins accepting proposals for this BAA.
However, until June 6, 2018, proposers may still submit written questions about solicitation topics through the DoD's SBIR/STTR Interactive Topic Information System (SITIS), in which the questioner and respondent remain anonymous and all questions and answers are posted electronically for general viewing until the solicitation closes. All proposers are advised to monitor SITIS during the Open BAA period for questions and answers and other significant information relevant to their SBIR/STTR topics of interest.
Topics Search Engine: Visit the DoD Topic Search Tool at sbir.defensebusiness.org/topics/ to find topics by keyword across all DoD Components participating in this BAA.
Proposal Submission: All SBIR/STTR Proposals must be submitted electronically through the DoD SBIR/STTR Electronic Submission Website, as described in the Proposal Preparation and Submission of Proposal sections of the program Announcement.
Help: If you have general questions about DoD SBIR program, please contact the DoD SBIR Help Desk at 800-348-0787 or via email at email@example.com