  The Gemini Planet Imager (GPI) is an integral field spectrograph (IFS) and
coronagraph that is one of the few current generation instruments optimized for
high-contrast direct imaging of substellar companions. The instrument is in the
process of being upgraded and moved from its current mount on the Gemini South
Observatory in Cerro Pachon, Chile, to its twin observatory, Gemini North, on
Mauna Kea (a process colloquially dubbed 'GPI 2.0'). We present the designs
that have been developed for the part of GPI 2.0 that pertains to upgrading
various optical components of the GPI coronagraphic system. More specifically,
we present new designs for the apodizer and Lyot stop (LS) that achieve better
raw contrast at the inner working angle of the dark zone as well as improved
core throughput while retaining a similar level of robustness to LS
misalignment. To generate these upgraded designs, we use our own publicly
available software package called APLC-Optimization that combines a commercial
linear solver (Gurobi) with a high contrast imaging simulation package (HCIPy)
in order to iteratively propagate light through a simulated model of an
apodized phase lyot coronagraph (APLC), optimizing for the best coronagraph
performance metrics. The designs have recently finished being lithographically
printed by a commercial manufacturer and will be ready for use when GPI 2.0
goes on-sky in 2023.
