A planar lightwave circuit device includes one or more planar lightwave
circuits (PLCs) each having an optical layer deposited on a substrate,
and a package base including one or more support structures for
suspending the planar lightwave circuit above a portion of the package
base. Each substrate has a first coefficient of thermal expansion,
whereas the package base has a second coefficient of thermal expansion.
The first and second coefficients of thermal expansion differ such that a
change in temperature causes the support to apply one of a compressive
and a tensile force to the planar lightwave circuit in a plane within or
parallel to the plane of the planar lightwave circuit. The induced stress
can modify the optical performance of the PLC device, e.g. to reduce the
temperature sensitivity of the device and thus maintain device
performance, or for providing efficient passive or dynamic tuning of the
device.