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arXiv · 1209.5264

Periodically patterned columnar thin films as Blazed gratings

Jhuma Dutta·S. Anantha Ramakrishna·Akhlesh Lakhtakia
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Abstract

Periodically patterned columnar thin films (PP-CTFs) were made by evaporating CaF2 and directing the vapor flux obliquely towards lithographically fabricated micrometer/sub-micrometer gratings. The growth of the PP-CTFs was controlled by the deposition rate to form prismatic air cavities within them and they function like blazed diffraction gratings with asymmetric diffraction patterns and diffraction efficiencies upto 52% in transmission at visible wavelengths. Scalar diffraction theory qualitatively explained the measured diffraction efficiencies.

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Jhuma Dutta, S. Anantha Ramakrishna, Akhlesh Lakhtakia. 2012-09-24. Periodically patterned columnar thin films as Blazed gratings. https://doi.org/10.1063/1.4802975

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