Open AccessLow loss coupling to sub-micron thick rib and nanowire waveguides by vertical tapering
Author(s) -
Steve Madden,
Zilong Jin,
DukYong Choi,
Sukanta Debbarma,
Douglas Bulla,
Barry LutherDavies
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.003582
Subject(s) - tapering , materials science , optics , waveguide , photonic crystal fiber , coupling loss , optical fiber , planar , insertion loss , attenuation , coupling (piping) , nanowire , optoelectronics , wavelength , composite material , physics , computer graphics (images) , computer science
Highly nonlinear planar glass waveguides have been shown to be useful for all optical signal processing. However, the typical SMF-28 fiber to waveguide coupling loss of ~5dB/end remains a barrier to practical implementation. Low loss coupling to a fiber using vertical tapering of the waveguide film is analyzed for rib and nanowire waveguides and experimentally demonstrated for ribs showing polarization and wavelength independence over >300nm bandwidth. Tapers with essentially zero excess loss led to total losses from the waveguide to fiber core of 1.1dB per facet comprising only material absorption (0.75dB) and mode overlap loss (0.36dB), both of which can be eliminated with improvements to processing and materials.