Modeling of an Optical Black Hole with True Gaussian Beam Incidence

X. Ni[1], A. Kildishev[1], E. Narimanov[1], and L. Prokopeva[2]
[1]Purdue University, West Lafayette, IN, USA
[2]Russian Academy of Sciences, Novosibirsk, Russia
Published in 2010

We model an ideal optical black hole device in COMSOL Multiphysics as an electromagnetic scattering problem. The device is illuminated with a Gaussian beam which is focused at a fixed position in horizontal direction (x0) and different positions in vertical direction (y0). The device is modeled as a cylindrical system with a gradient-index shell and absorbing core. Using the classical paraxial approximation for the Gaussian beam stimulates unphysical background scattering because the function is not an exact solution of the Maxwell’s equations. To solve the problem, a plane wave expansion is used as the incident field in the model, which yields an accurate description of the Gaussian beam. The beam is passing-by when it is away from the optical black hole device. The beam is partially absorbed by the devices when it is touching the boundary, and the beam gets totally absorbed into core when it hits right on the device. FE simulations with COMSOL are compared to the results obtained from an analytical calculation scheme and a perfect match is observed.

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