N241-066 TITLE: Laser Magazine

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Directed Energy (DE)

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 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 a compact, battery powered, uncooled, tens of kilowatt (tens of kW), one micron wavelength, high energy laser (HEL) integrated solid state laser (SSL) subsystem utilizing concepts such as a reloadable magazine "clip", or "replaceable" rechargeable, man serviceable, cooling and battery magazines. These "replacement" magazines offer an opportunity to forgo "near infinite life" requirements and examine the potential benefits of limited life (tens to hundreds of shots) and potentially expendable, quickly replaceable munition type power and cooling sub-assemblies.

DESCRIPTION: For the Navy and Marine Corps, the demand on "infinite duty cycle" cooling by water chillers deteriorates causing limited operational employment. Relieving the design and alignment constraints of separating the systems and examining "rechargeable magazines" for cooling and electrical power in the deployment of such kW-class HEL systems may have benefits on small platforms (ground or airborne, including unmanned weapon platforms) and offers some unique research opportunities. The Navy seeks development of a solid state laser that is compact, battery powered, uncooled and on the order of tens of kilowatts (kW) operating at one micron wavelength, and able to produce continuous wave high energy laser (HEL) energy as an integrated subsystem.

Currently, prototype HEL systems are being deployed in a variety of platforms as laser weapons; prototype systems have been deployed by the Navy platforms as laser weapons to destroy targets and threats. These are each separately developed subsystems (power, cooling, laser) – but the interest is a combined small size, weight, and integrated power with cooling (SWaP-C) for tens of kilowatt class HEL systems limit utility from those combined systems. Use of systems that are "direct diode" or "pixel/vixel" based are of primary interest, possibly using coherent, spectral, or incoherent power beam combination techniques due to their inherent high efficiency, whereas fiber or other gain amplification systems are seen as less efficient and require higher levels of optical integration risk.

For the Navy and Marine Corps, the demand on "infinite duty cycle" cooling by water chillers deteriorates causing limited operational employment. Relieving the design and alignment constraints of separating the systems and examining "rechargeable magazines" for cooling and electrical power in the deployment of such kW-class HEL systems may have benefits on small platforms (ground or airborne, including unmanned weapon platforms) and offers some unique research opportunities.

Using the same concept as a reloadable magazine "clip", this SBIR topic seeks innovation in "replaceable" rechargeable, man serviceable, cooling and battery magazines. These "replacement" magazines offer an opportunity to forgo "near infinite life" requirements and examine the potential benefits of limited life (tens to hundreds of shots) and potentially expendable, quickly replaceable munition type power and cooling sub-assemblies. The Navy seeks a compact battery powered, uncooled, tens of kilowatt (10’s of kW), one micron wavelength, HEL integrated solid state laser (SSL) subsystem. High cooling capacity and thermal requirements have driven HELs to focus on water chilled systems that are heavy and operate within tight tolerances for temperatures. The potential to dissipate the heat generated by the laser amplifier medium and externally pump, or exhaust, the resulting heat from the sources of heat - to areas or materials that dissipate the heat, have only been explored to a limited extent. Similarly, the potential to "dump" heat (for example, by exhaust or release of superheated water vapor) are seldom contemplated. However, in some circumstances, this may be a preferable and acceptable trade for the purposes of reducing subsystem weight.

The DoD has a great demand for compact and robust unmanned weapon platforms. Therefore, DoD has a resulting great demand for more compact and robust uncooled kilowatt - class laser systems for a variety of short time use cases and applications, if temperature tolerant designs for one micron wavelength lasers can be found. Industry will benefit as class laser system for a variety of short duty cycle power and thermal applications, as well from the reduced well SWaP-C requirements for technology in applications where lasers are used to cut, weld, or ablate and clean substrates with limited surface areas. At present, an air cooled, compact battery power kW class HEL system is not a known commercially available item used with laser subsystems.

KEY PARAMETERS – Laser Magazine

Power Threshold: 10 kW (Objective: 20 kW); ability to focus light at a range of kilometers with minimal atmospheric turbulence (Cn2

HEL wavelength: one (1) Micron (1020-1095 um)

Technology: Solid State Laser (Preference for high efficiency laser semiconductor based diodes or similar pixel LED emitters)

Laser beam output quality (M2): Threshold: 2, (Objective < 1.4, vertical & horizontal, Gaussian or top hat.)

Laser Weight: Threshold: 120 lbs (Objective 20 lbs)

Volume: Threshold: 50 cubic inches (Objective < 20 cubic inches);

Air cooled compact HEL prototyped system with input air 60°C and 90% humidity

Audible Noise: under 60 dB

Operating Temperature: Threshold: 15°C to 30°C, Objective 10°C to 70°C

Work produced in Phase II may become classified. Note: The prospective contractor(s) must be U.S. owned and operated with no foreign influence as defined by 32 U.S.C. § 2004.20 et seq., National Industrial Security Program Executive Agent and Operating Manual, unless acceptable mitigating procedures can and have been implemented and approved by the Defense Counterintelligence and Security Agency (DCSA) formerly Defense Security Service (DSS). The selected contractor must be able to acquire and maintain a secret level facility and Personnel Security Clearances. This will allow contractor personnel to perform on advanced phases of this project as set forth by DCSA and ONR in order to gain access to classified information pertaining to the national defense of the United States and its allies; this will be an inherent requirement. The selected company will be required to safeguard classified material during the advanced phases of this contract IAW the National Industrial Security Program Operating Manual (NISPOM), which can be found at Title 32, Part 2004.20 of the Code of Federal Regulations. Reference: National Industrial Security Program Executive Agent and Operating Manual (NISP), 32 U.S.C. § 2004.20 et seq. (1993). https://www.ecfr.gov/current/title-32/subtitle-B/chapter-XX/part-2004

PHASE I: Develop a concept for an innovative laser magazine. Validate the product-market fit between the proposed solution and with the Navy stakeholder define a clear plan for trial and/or test with the proposed solution and the focus area.

The proposed solution should directly address:

1. Identify the components and likely configuration and explore the extents of the benefit area(s) compared to identified objectives, which are to be addressed by the proposed solution(s),

2. Define clear objectives and measurable figures of merit for the proposed solution(s) – specifically how the proposed solution(s) will be developed into a compact subassembly or "laser magazine,"

3. Define any inherent risks to achieving objectives and measurable figures of merit for the proposed solution(s) as well as potential risk mitigation strategies,

4. Describe the cost and feasibility of integration with current mission-specific subsystems,

5. Describe how the component or solution(s) can be used by other government customers, both DoD and non-DoD, and the impacts of "expendable" solutions, and

6. Describe technology related development that is required to successfully field the proposed solution(s) with a preliminary set of incremental - steps or milestones over subsequent phases of the effort.

PHASE II: Develop, integrate, and demonstrate a prototypical laser magazine (unit) in a laboratory environment, as determined to be the most feasible solution during the Phase I period. The demonstration should focus on:

1. Evaluating the proposed solution against the operational system requirements, objectives and measurable results as defined in Phase I

2. Describing in detail how the solution can be scaled to be adopted widely

3. A clear transition path for the proposed solution that takes into account input from stakeholders

4. Specific details on how the proposed solution can be integrated and how it will be supported/sustained

5. Laboratory experimentation, with incremental and final technical reports.

Work in Phase II may become classified. Please see note in the Description.

PHASE III DUAL USE APPLICATIONS: Make additional improvements in manufacturing and development of a compact size demonstrator at a scale showing laser performance with focus on manufacturing methods to continue to improve component packaging, yield, production time, and individual component contributions to size, performance, and cost. Criterion for the laser performance in Phase III is dependent on the progress made in Phase II. New criterion for Phase III includes the time and cost to produce small quantities (100), and individual first unit components.

Small, miniature laser magazines offer potential in multiple commercial applications including remote sensing, metal fabrication/cutting, and for long range telecommunications or remote powering. There is some potential for some solid-state lasers developed to be used in a next generation laser weapon system, which have less dependency on physical and environmental challenges seen with current systems.

REFERENCES:

1. Rothenberg, J. "Limits of Power Scaling by fiber based optical amplifiers, fiber laser combination" Optical Fiber Communications (OFC), 2009 high power fiber laser workshop, 23 March 2009
2. Denker, B. and Shklovsky, E. (eds.) "Handbook of Solid-State Lasers: Materials, Systems and Applications." Woodhead Publishing, 2013
3. Bowman, S.R.; Jenking; N.W.; O'Connor, S.R.; and Feldman, B.J. "Sensitivity and stability of a radiation-balanced laser system," IEEE Journal of Quantum Electronics, Volume 38, Issue 10, October 2002, pp, 1339 – 1348. DOI: 10.1109 / JQE.2002.802950
4. Bahari, Babak; Vallini, Felipe; El Amili, Abdelkrim and Kante, Boubacar. "Nonreciprocal lasing in topological cavities of arbitrary geometries." SCIENCE Vol. 358, No. 6363, p. 636. DOI: 10.1126
5. Bao, L.; Bai, et al. "Reliability of High Power/Brightness Diode Lasers Emitting from 790 nm to 980 nm." Proc. of SPIE 8605, 860523 (2013).
6. Chow, W.W. and Koch, S.W. "Semiconductor-Laser Fundamentals Physics of the Gain Materials." Springer, Berlin, 1999.
7. Coldren, L.A. and Corzine, S.W. "Diode Lasers and Photonic Integrated Circuits." John Wiley & Sons, New York, 1995.

KEYWORDS: Laser, photon, light, battery, cooling

---