We complete the 'paraxial' (small-angle) ray optics cloaking formalism presented previously [Opt. Express 22, 29465 (2014)], by extending it to the full-field of light. Omnidirectionality is then the only relaxed parameter of what may be considered an ideal, broadband, field cloak. We show that an isotropic plate of uniform thickness, with appropriately designed refractive index and dispersion, can match the phase over the whole visible spectrum. Our results support the fundamental limits on cloaking for broadband vs. omnidirectionality, and provide insights into when anisotropy may be required.
Bibliographical noteFunding Information:
The authors would like to thank Professor Allan Greenleaf for background on Calderon''s inverse problem and uniqueness theorems, and Professor James Fienup for discussions on field propagation. This work was supported by the Army Research Office Grant No. W911 NF-12-1-0263 and the DARPA DSO Grant No. W31P4Q-12-1-0015. J.S.C was also supported by a Sproull Fellowship from the University of Rochester.
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