Adv. Mater. 2010, 22, 2561–2564 2010 WILEY-VCH Verlag G T IO N In Roman mythology, the god Janus was depicted with two faces, looking in opposite directions. This led to the phrase ‘‘Janus faced’’ which is mostly used for a ‘‘two-faced’’ or deceitful character of a person. Within integrated photonics a concept like Janus can provide a new class of multi-functional optical meta-elements which co...

Gradient index structures are gaining increased importance with the constant development of Transformation Optics and metamaterials. Our ability to fabricate such devices, while limited, has already demonstrated the extensive capabilities of those designs, in the forms of invisibility devices, as well as illusion optics and super-lensing. In this paper we present a low loss, high index contrast...

We describe the results and objectives of a research line to develop Lie-algebraic and grouptheoretic methods for the study of optics with aberration . We have applied REDUCE programming to obtain the phase-space transformation due to the refracting interface between two media, using a recent result on factorisation into a simpler "root" transformation. The latter is given by a pair of implicit...