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arXiv · 1111.4324

Controllable coherent perfect absorption in a composite film

Shourya Dutta-Gupta·Olivier J. F. Martin·S. Dutta Gupta·G. S. Agarwal
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Abstract

We exploit the versatility provided by metal--dielectric composites to demonstrate controllable coherent perfect absorption (CPA) in a slab of heterogeneous medium. The slab is illuminated by coherent light from both sides, at the same angle of incidence and the conditions required for CPA are investigated as a function of the different geometrical parameters. The simultaneous realization of CPA at two distinct frequencies is also shown. Finally, our calculations clearly elucidate the role of absorption as a necessary prerequisite for CPA.

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Shourya Dutta-Gupta, Olivier J. F. Martin, S. Dutta Gupta, G. S. Agarwal. 2011-11-18. Controllable coherent perfect absorption in a composite film. https://doi.org/10.1364/oe.20.001330

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