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Probing the dispersive and spatial properties of planar photonic crystal waveguide modes via highly efficient coupling from optical fiber tapers

Paul E. Barclay·Kartik Srinivasan·Matthew Borselli·Oskar Painter
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Abstract

The demonstration of an optical fiber based probe for efficiently exciting the waveguide modes of high-index contrast planar photonic crystal (PC) slabs is presented. Utilizing the dispersion of the PC, fiber taper waveguides formed from standard silica single-mode optical fibers are used to evanescently couple light into the guided modes of a patterned silicon membrane. A coupling efficiency of approximately 95% is obtained between the fiber taper and a PC waveguide mode suitably designed for integration with a previously studied ultra-small mode volume high-Q PC resonant cavity [1]. The micron-scale lateral extent and dispersion of the fiber taper is also used as a near-field spatial and spectral probe to study the profile and dispersion of PC waveguide modes. The mode selectivity of this wafer-scale probing technique, together with its high efficiency, suggests that it will be useful in future quantum and non-linear optics experiments employing planar PCs.

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Paul E. Barclay, Kartik Srinivasan, Matthew Borselli, Oskar Painter. 2003-08-12. Probing the dispersive and spatial properties of planar photonic crystal waveguide modes via highly efficient coupling from optical fiber tapers. https://doi.org/10.1063/1.1767954

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