Exciting surface plasmons with transformation media

The final publication is available at Springer via http://dx.doi.org/10.1007/s11468-012-9361-5 We present a way of exciting surface plasmon polaritons along non-patterned metallic surfaces by means of a flat squeezing slab designed with transformation optics. The slab changes the dispersion relation of incident light, enabling evanescent coupling to propagating surface plasmons. Unlike prism couplers, the proposed device does not introduce reflections at its input interface. Moreover, its compact geometry is suitable for integration. A feasible dielectric implementation of the coupler is suggested. Finally, we show that the angular response of the device can be engineered by using a non-uniform compression factor. As an example, we design a coupler with a half-power angular bandwidth 2. 5 times higher than that of a conventional dielectric coupler. © 2012 Springer Science+Business Media, LLC. Financial support by Spanish Ministerio de Ciencia e Innovacion (contracts CSD2008-00066 and TEC2008-06871-C02, and FPU grant) is gratefully acknowledged. García Meca, C.; Ortuño Molinero, R.; Martí Sendra, J.; Martínez Abietar, AJ. (2012). Exciting surface plasmons with transformation media. Plasmonics. 7(4):701-707. https://doi.org/10.1007/s11468-012-9361-5 Raether H (1988) Surface plasmons on smooth and rough surfaces and on gratings. Springer-Verlag, Berlin Barnes WL, Dereux A, Ebbesen TW (2003) Surface plasmon subwavelength optics. Nature 424:824–830 Maier SA (2007) Plasmonics: fundamentals and applications. Springer, New York Schuller JA, Barnard ES, Cai W, Jun YC, White JS, Brongersma ML (2010) Plasmonics for extreme light concentration and manipulation. Nat Mater 9:193–204 Brongersma ML, Shalaev VM (2010) The case for plasmonics. Science 328:440–441 Liu Y, Zentgraf T, Bartal G, Zhang X (2010) Transformational plasmon optics. Nano Lett 10:1991–1997 Huidobro PA, Nesterov ML, Martín-Moreno L, García-Vidal FJ (2010) Transformation optics for plasmonics. Nano Lett 10:1985–1990 Kadic M, Guenneau S, Enoch S (2010) Transformational plasmonics: cloak, concentrator and rotator for SPPs. Opt Express 18:12027–12032 Zhang J, Xiao S, Wubs M, Mortensen NA (2011) Surface plasmon wave adapter designed with transformation optics. ACS Nano 5:4359–4364 Pendry JB, Schurig D, Smith DR (2006) Controlling electromagnetic fields. Science 312:1780–1782 Leonhardt U (2006) Optical conformal mapping. Science 312:1777–1780 Leonhardt U, Philbin TG (2006) General relativity in electrical eng