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arXiv · 1510.06344

Near-to-far field transformations for radiative and guided waves

Jianji Yang·Jean-Paul Hugonin·Philippe Lalanne
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Abstract

Light emitters or scatterers embedded in stratified media may couple energy to both free space modes and guided modes of the stratified structure. For a comprehensive analysis, it is important to evaluate the angular intensity distribution of both the free-space modes and guided modes excited in such systems. In the present work, we propose an original method based on Lorentz-reciprocity theorem to efficiently calculate the free-space and guided radiation diagrams with a high accuracy from the sole knowledge of the near-field around the emitters or scatterers. Compared to conventional near-to-far field transformation techniques, the proposal allows one to easily evaluate the guided-mode radiation diagrams, even if material dissipation is present in the stack, and thus to simultaneously track the coupling of light to all channels (i.e., free-space and guided-ones). We also provide an open-source code that may be used with essentially any Maxwell's equation solver. The numerical tool may help to engineer various devices, such as light-emitting diodes or nanoantennas to achieve directional and efficient radiative spontaneous decays in free space and guided optics.

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Jianji Yang, Jean-Paul Hugonin, Philippe Lalanne. 2016-01-18. Near-to-far field transformations for radiative and guided waves. https://doi.org/10.1021/acsphotonics.5b00559

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