Air Force Research Laboratory – Directed Energy Materials Program: High Energy Lasers Fiber Development and Improvement

The US Air Force is in pursuit of materials technology advances for directed energy systems for high energy laser (HEL) systems, high power microwave (HPM) systems and mid-infrared laser source and laser development.

Materials advances for high energy lasers in the kilowatt range including new fiber laser materials, advances in current fiber laser materials and development of materials for high power optical isolation in fiber lasers is desired.

High power microwave systems require improvements in window materials to address window technology development for HPM systems. Particularly, pursuit of optical diamond for improved strength and toughness with lower cost production capability is desired. Additionally, for other HPM applications, improvements in window durability and optical transmission are desired to yield decreased absorption and reflection loss for the transmission of 300 megawatts of microwave power.

Multiple contract awards are anticipated with various dollar values. Contract periods of performance are anticipated to be for 36 months plus 3 months for final reports. The Directed Energy Materials Program is being initiated via release of this BAA Number 09-11-PKM announcement. This announcement describes the overall program. Calls to the BAA/solicitation will be issued to request cost and technical proposals for specific Directed Energy Materials technologies in one or more of the following technical areas: High Energy Laser Materials, including High Energy Laser Fibers Development and Improvement and Optical Isolation, Mid-Infrared Laser Source and Laser Development, and High Power Microwave Windows. BAA Calls will contain descriptions of the Directed Energy Materials efforts to be addressed, anticipated period of performance, and the expected dollar range for requested proposals. Once a BAA Call is issued on the Federal Business Opportunities (FedBizOpps) website, offerors will have 30 to 45 calendar days (the actual period will be specified in the BAA Call(s)) from the announcement date to submit cost and technical proposals. Proposals received outside of the set forth period (i.e. a BAA Call already issued and the proposal due date has passed, or a BAA Call has not yet been issued) will not be reviewed and will be returned to the offeror. NOTE: Proposal receipt after the due date and time shall be governed by the provisions of FAR 52.215-1(c)(3). Multiple BAA Calls are anticipated and may be announced sequentially or concurrently. The Government also reserves the right to make no award against any subsequent BAA Call.

Address technical questions to: William Mitchell, 3005 Hobson Way, Wright-Patterson AFB, OH 45433, 937-255-9583, William.Mitchell@wpafb.af.mil.

CALL 1: High Energy Lasers Fiber Development and Improvement.
Rare-earth Doped YAG Fiber Development
To this end, development of rare earth doped-YAG fiber, either single crystal or polycrystalline. Preferred doping material is Ytterbium but other rare earths are acceptable for fiber development demonstration. Development and demonstration of laser operation in single mode is strongly preferred. Co-development of processes and techniques for outer cladding layers is also desirable to include support for cladding-pumped schemes for fiber lasers. Desired goals for this effort include core diameters on the order of 25 microns, first cladding yielding 100-150 micron total diameter, 1-3 meter lengths as a demonstration goal, fibers exhibiting spoolability, and beam quality measures of 1-1.2 M-squared.

Silica-based Fiber Technology Improvement
The development of materials improvements to increase power handling in silica-based fibers, particularly in single mode operation, is of interest. Reduction in nonlinear effects such as stimulated scattering, (Brillouin, Raman) through materials improvements, improved fiber uniformity in doping, thickness variation, cladding interfaces and other critical issues relation to fiber performance are desired.