70-nm-bandwidth achromatic waveguide coupler.
We report a general approach to the design of broadband waveguide couplers. A double-parallel grating assembly is used to cancel the first chromatic order, and a proper choice of prism glass and base angle is made to compensate for the second chromatic order. The technique was applied to a Corning glass 7059 waveguide, and a spectral bandwidth of 70 nm was measured by the use of two complementary procedures.
S B
SB
Mendes
L
L
Li
J J
JJ
Burke
J E
JE
Lee
S S
SS
Saavedra