|Acquisition Program: ||PM Future Combat Systems Brigade Combat Team|| Objective: ||Develop a compact and rugged ultrafast laser system capable of advanced spectroscopic methods for detection of hazardous battlefield materials at a distance.
|| Description: ||Currently, the detection of hazards (e.g. explosives)at range suffer from a lack of sensitivity and selectivity due to the inability to receive signals that provide both the necessary strength and requisite information to delineate the threats from background materials. Recent research is examining advanced spectroscopy methods that utilize Quantum Control techniques as a means to overcome these shortcomings. Demonstrations have proven that detection strategies using these techniques could represent the next generation of stand-off battlefield sensors (1,2). These demonstrations are based on the ability to manipulate the inherent pulse shape of the laser excitation through frequency domain techniques. These manipulations currently rely on the bandwidth provided by large laboratory-scale Titanium-Sapphire laser sources. Development of the next-generation sensor systems requires a more compact and robust laser source not currently available. This laser source should provide ultrafast characteristics ( pulsewidth less than 100 femtoseconds, optical bandwidth 10 nanometers or greater and energy/pulse greater than 100 micro-Joules ) similar to laboratory system being used in sensor demonstrations. Several routes toward these specifications are potentially available (e.g. fiber laser), but many technical hurdles due to the impact from high order dispersion and gain narrowing effects have limited development to sub-picosecond pulse-width and/or few micro-joule energy levels.(3,4)
|| ||PHASE I: Develop a design for a compact, rugged ultrafast laser with high output energy in excess of 100 micro-Joules per pulse and pulse width below 100 femtoseconds equating to a bandwidth in excess of 10 nanometers assuming time-bandwidth-limited pulse properties. Predicted performance should meet optical specification mentioned for above, but also strive to design system with a volume less than 1 cubic meter in size, a weight less than 100Kg and power consumption under 600 Watts.
|| ||PHASE II: Develop, test and demonstrate a prototype laser with required specifications as mentioned in Phase I. Required Phase II deliverables will include prototype, test report and OME cost for manufacture.
|| ||PHASE III: Based on Phase II results, a minimum of two laser systems should be fabricated and characterized. These laser systems will be used to demonstrate manufacturability and to validate the fabrication process and performance. A series of demonstration tests shall be conducted to verify performances.
These laser systems can be used for multiple Military applications including: stand-off detection of chemical, biological and explosives materials being examined within Army programs[ e.g. ATO R.ECB.2010.01 (Detection of Unknown Bulk Explosives)]. Commercial applications of this laser technology include analog sensing at range, but also include potential laser sources for tailored photofragmentation for Mass Spectroscopy, Laser Machining and Biomedical Engineering. The technical POCs for the phase I and II efforts will pursue further research and development funds in phase III in line with current ATO-R efforts, follow-on ATO-D and complimentary programs within the DTRA's CBRNE portfolio.
|| References: ||
1. "Quantum Control of Tightly Competitive Product Channels," Roth, M; Guyon, L; Roslund, J, et al., PHYS.REV.LETTERS Vol. 102, 25 Art. No.253001(2009)
2. "Single-beam coherent anti-Stokes Raman scattering spectroscopy of N-2 using a shaped 7 fs laser pulse," Roy, S; Wrzesinski, P; Pestov, D, et al., APPL. PHYS. LETTERS Vol.95,7 Art. No.074102(2009)
3. "Femtosecond fiber CPA system with 325 W average power," Eidam, T.; Roser, F.; Seise, E., et al., Fiber Lasers VI: Technology, Systems, and Applications, San Jose, CA USA, Proc. of SPIE, 719514 (2009).
4. F. Roser, et al., mJ pulse energy high repetition rate fs fiber CPA system, Opt. Lett. 32, 3495 (2007).
|Keywords: ||femtosecond laser, ultrafast laser, fiber laser, quantum control, laser spectroscopy, hazardous material detection, laser amplifiers|