TECHNOLOGY AREAS: Ground/Sea Vehicles, Materials/Processes

ACQUISITION PROGRAM: CG(X) Program Office (PMS 502); Integrated Topside INP

OBJECTIVE: Using metamaterial technology, develop and demonstrate thin films in which the reflectivity and emissivity can be tailored and controlled over a large range.

DESCRIPTION: Metamaterials are engineered composites that exhibit superior properties not found in nature and not observed in the constituent materials. Electromagnetic metamaterials exhibiting negative refraction show promise for a variety of optical and microwave applications such as new types of beam steerers, modulators, band-pass filters, lenses, microwave couplers, and antenna radomes. Laboratory demonstrations of negative refraction have been limited to small areas due to laborious fabrication techniques. Practical application of metamaterials for large area coatings will require use of scalable manufacturing such as film processes. The purpose of this topic is demonstrate thin films exhibiting electromagnetic responses characteristic of metamaterials, such as negative refraction, in the visible-infrared spectral region (0.3 � 10 microns wavelength). Films can be made of any combination of constituent materials. The successful proposal will give details of the modeling, design, fabrication and testing methodologies to be used, as well as a discussion of recent scientific literature relating to these materials. The successful proposal will include at least one novel fabrication approach that holds promise for making films having an area of at least a square foot.

PHASE I: Demonstrate the feasibility of designing and fabricating a metamaterial film in which the reflectivity and emissivity can be tailored from low to high values. Determine the bandwidth, loss, and effect of angle of incidence on reflectance and transmittance. Analyze the scalability of fabrication to large areas in Phase II

PHASE II: Develop large (greater than a square foot) prototype films or coatings based on the success of the Phase I work. Develop methods to increase bandwidth. Extend fabrication to multi-layered films. Extend Phase I analysis in order to determine tradeoffs between bandwidth, loss, and angular response.

PHASE III: Develop prototype production line for the fabrication of large area metamaterial films and commercialization plans using the knowledge gained during Phases I and II.

PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: The development of large area films could be used as anti-reflective coatings in numerous commercial applications.

REFERENCES:
1. V. M. Shalaev and A. K. Sarychev, Electrodynamics of Metamaterials, World Scientific Publishing Company (2007).

2. N. Engheta and R.W Ziolkowski, Electromagnetic Metamaterials: Physics and Engineering Explorations, Wiley-IEEE Press (2006).

3. J. Valentine, et al., "Three-dimensional optical metamaterial with a negative refractive index," Nature 455, 376 (2008).

4. A. Alù and N. Engheta, "Dynamical theory of artificial optical magnetism produced by rings of plasmonic nanoparticles," Phys. Rev. B 78, 085112 (2008).

KEYWORDS: metamaterials, negative refraction, electromagnetic materials, thin film processing