Program Manager: Jamil
R. Abo-Shaeer, Ph.D.
 The vision of DARPA's Negative Index Materials (NIM) program is to further understand and explore the physics of left-handed transport and negative refractive index and to significantly expand the frequency range at which these phenomena are observed. Materials with left handed/negative index behavior were first postulated in 1967 when a Russian theorist, Veselago, published a paper in which he considered the electrodynamics of materials with simultaneously negative dielectric permittivity and magnetic permeability. In this paper Veselago predicted a number of properties for such a material, should it exist, including the following: (1) the material would exhibit a negative index of refraction, in contrast to conventional materials that exhibit a positive index of refraction; and (2) the material would exhibit "left-handed" propagation of electromagnetic waves meaning that the phase and group velocities would be directionally opposed. However, it was not until 2000 that the first reports of a "left-handed" or "negative index" material were published. Since that time many of Veselago's original predictions have been verified experimentally or through extensive simulation. Having confirmed the existence of negative refraction in resonant RF structures with negative permittivity and permeability, researchers are now postulating many exciting new DoD-relevant applications for these materials.
Exploring the possible implementation of negative index materials for DoD applications will require significant enhancements in the properties of existing NIM (bandwidth, loss, operational frequency, etc.), as well as improved understanding of the physics of their electromagnetic transport properties. Specific technical objectives of DSO's NIM program include the following: (1) verify experimentally and further understand the physics and consequences of opposing group and phase velocities in negative index materials; (2) explore and demonstrate sub wavelength imaging using negative index materials; (3) expand the operational frequency range of negative index materials; and (4) understand and reduce the loss mechanisms of negative index materials for practical application. It is envisioned that advances in NIM may lead to a number of exciting DoD-relevant applications including lightweight, compact RF structures and improved optics for imaging systems.
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