Description:
TECHNOLOGY AREA(S): Materials
OBJECTIVE: This STTR effort seeks to investigate novel approaches using multilayered hybrid 2-dimensional nanostructures as passive coatings and evaluate their interactions with high energy lasers.
DESCRIPTION: As part of the continuous transformation of the US Armed forces to be endowed with new, advanced and effective military capabilities it is an unequivocal paradigm to eradicate, minimize and mitigate vulnerabilities from them as well. The development of protection and hardening mechanisms against directed energy weapons such as high energy lasers are necessarily critical requirements for the progression of effective countermeasures [1]. High energy lasers (HELs) possess certain unique attributes such as speed of light response, precision strikes, reduced collateral damage, and potentially low cost per kill. They have the potential to cause damage or disable electronic components, sensors, optics, and structural components of advanced armaments, thereby disabling their effectiveness in completing intended missions. Many approaches, including chemical lasers, fiber lasers, solid state lasers, and free electron lasers, are available to build HELs, and many impediments to their deployment are steadily being overcome. Commensurate with the advances in HELs as directed energy weapons, it is imperative that parallel advances are required for protection against them, as well as to achieve an asymmetrical advantage over the adversaries. This topic endeavors, in particular, to research schemes for understanding fundamental high energy laser interactions with exploratory photonic material structures and designs.
PHASE I: Investigate novel approaches using multilayered hybrid 2-dimensional nanostructures as passive coatings and evaluating their interactions with high energy lasers. In particular, the aim is to design photonic designs of 2D metallic/inorganic/organic materials wherein disorder in the structure may be used to affect significant extinction and/or reflection of high energy coherent beams. In this regard, photonic glass with and without self-similar structures (fractals) could be advantageous as an additional variable to manipulate the incident radiation. At the end of Phase I, areas for further detailed investigation during Phase II should be identified.
PHASE II: Detailed physics based models will be developed for understanding the material interactions with high energy radiation using disorder in multilayered hybrid 2-dimensional nanostructures. Non-linear materials, photonic band structure designs, nanoporous compositions, self-similar structures, etc., can be considered as part of the design space. The design will also consider the effects of variables such as the angle of incidence, beam quality and polarization effects, if any, of the incident radiation. It can be assumed that the radiation is in the visible to near IR wavelength range with target irradiances in the range of tens to hundreds of kilowatts per cm2. Thin film material structures may be supported on appropriate substrates that take into account mechanical, thermal and other constraints. Fundamental material attributes will be developed for comparing the efficacy of the various nanostructure designs. Designs should be driven by final implementable solutions. The deliverables at the conclusion of the Phase II effort would include a fundamental understanding of the material interactions with high energy lasers.
PHASE III: Phase III will entail further research and refinement of the designs of Phase II along with modeling and simulation towards advancing the knowledge of material interactions with high energy lasers. The effort through all the phases will be coordinated with the stakeholders in all the three services which will facilitate definition of the requirements and transition of the technology. Strategic partnerships will be developed to further the commercialization potential of the technology.
REFERENCES:
1: Defense Science Board Task Force on Directed Energy Weapons, Office of the Under Secretary of Defense for Acquisition, Technology and Logistics, Washington D.C. Dec. 2007.
2: A. F. Koenderink and W. L. Vos,Optical properties of real photonic crystals: anomalous diffuse transmission, J. Opt. Soc. Am. B, 22, 1075-1083, 2005.
3: J.A. Bossard, L.Lin and D.H. Werner Evolving random fractal Cantor superlatttices for the infrared using a genetic algorithm, J. R. Soc. Interface 13, 0975, 2015.
4: V.M. Shalaev, ed. Optical properties of nanostructured random media. Vol. 82. Springer Science & Business Media, 2002.
KEYWORDS: Low Nanostructures, Photonic Designs Of 2D Metallic/inorganic/organic Materials, Self-similar Structures, Material Interactions With High Energy Lasers
