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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Zero-group-velocity modes in chalcogenide holey photonic-crystal fibers
Ardavan F Oskooi1, J D Joannopoulos, Steven G Johnson
1Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Abstract:
We demonstrate that a holey photonic-crystal fiber with chalcogenide-glass index contrast can be designed to have a complete gap at a propagation constant beta = 0 that also extends into the non-zero beta region. This type of bandgap (previously identified only at index contrasts unattainable in glasses) opens up a regime for guiding zero-group-velocity modes not possible in holey fibers with the more common finger-like gaps originating from beta-->infinity. Such modes could be used to enhance nonlinear and other material interactions, such as for hollow-core fibers in gas-sensor applications.
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