Phase front design with metallic pillar arrays

E. L. Ginzton Laboratory and Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
Optics Letters (Impact Factor: 3.29). 03/2010; 35(6):844-6. DOI: 10.1364/OL.35.000844
Source: PubMed


We demonstrate numerically, using a three-dimensional finite-difference frequency-domain method, the ability to design a phase front using an array of metallic pillars. We show that in such structures, the local phase delay upon transmission can be tuned by local geometry. We apply this knowledge to demonstrate a metallic microlens. The presented design principles apply to a wider range of wavelength-size integrated photonic components.

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Available from: Zhichao Ruan, Jul 28, 2015
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