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arXiv · 1112.0407

Nonlocal transformation optics

Giuseppe Castaldi·Vincenzo Galdi·Andrea Alu'·Nader Engheta
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Abstract

We show that the powerful framework of transformation optics may be exploited for engineering the nonlocal response of artificial electromagnetic materials. Relying on the form-invariant properties of coordinate-transformed Maxwell's equations in the spectral domain, we derive the general constitutive "blueprints" of transformation media yielding prescribed nonlocal field-manipulation effects, and provide a physically-incisive and powerful geometrical interpretation in terms of deformation of the equi-frequency contours. In order to illustrate the potentials of our approach, we present an example of application to a wave-splitting refraction scenario, which may be implemented via a simple class of artificial materials. Our results provide a systematic and versatile framework which may open intriguing venues in dispersion engineering of artificial materials.

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Giuseppe Castaldi, Vincenzo Galdi, Andrea Alu', Nader Engheta. 2011-12-02. Nonlocal transformation optics. https://doi.org/10.1103/physrevlett.108.063902

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