Artificial metamaterials – metallo-dielectric composites tailored on deep-subwavelength scale – enable implementation of electromagnetic responses not found in nature, leading to potentially useful applications as well as yielding new insights into the fundamental nature of light. Here we show how we have leveraged ultrasmooth planar nanoplasmonic waveguides deposited by ion-beam-assisted sputter deposition to implement easy-to-fabricate bulk metamaterials operating at visible and ultra-violet wavelengths and having refractive indices ranging from highly anisotropic and positive [1] to quasi-isotropic and negative [2]. Exploiting these structures to tailor the flow of light in exotic ways, we realize devices ranging from high-contrast, near-field nanoparticle optical sensors working in the visible, to the first implementation of a Veselago flat lens [3] functioning in the near ultraviolet. Substituting Al for Ag as the constituent plasmonic metal of choice, we investigate the extension of bulk metamaterial operation into the mid-ultraviolet, for lithographic applications beyond the diffraction limit.
[1] T. Xu and H.J. Lezec, Nat. Comm. 5, 4141 (2014). [2] T. Xu, A. Agrawal, M. Abashin, K.J. Chau, and H.J. Lezec, Nature 497, 470 (2013). [3] V.G. Veselago, Sov. Phys. Usp. 10, 509 (1968).
|