Experimental observations of a left-handed material that obeys Snell's law

Phys Rev Lett. 2003 Apr 4;90(13):137401. doi: 10.1103/PhysRevLett.90.137401. Epub 2003 Apr 3.

Abstract

We measure two-dimensional profiles of collimated microwave beams transmitted through composite wire and split-ring resonator prisms. Prior experiments suggest these structures have a negative index of refraction, though these claims have been questioned. Our 2D measurements demonstrate that transmission obeys Snell's law with a negative index, confirming the refractive nature of this signal and refuting alternatives posed in the criticisms. In addition, we present preliminary evidence that a flat rectangular slab of this material can focus power from a point source.