  HD 106906 is a young, binary stellar system, located in the Lower Centaurus
Crux (LCC) group. This system is unique among discovered systems in that it
contains an asymmetrical debris disk, as well as an 11 M$_{Jup}$ planet
companion, at a separation of $\sim$735 AU. Only a handful of other systems are
known to contain both a disk and directly imaged planet, where HD 106906 is the
only one in which the planet has apparently been scattered. The debris disk is
nearly edge on, and extends roughly to $>$500 AU, where previous studies with
HST have shown the outer regions to have high asymmetry. To better understand
the structure and composition of the disk, we have performed a deep
polarimetric study of HD 106906's asymmetrical debris disk using newly obtained
$H$-, $J$-, and $K1$-band polarimetric data from the Gemini Planet Imager
(GPI). An empirical analysis of our data supports a disk that is asymmetrical
in surface brightness and structure, where fitting an inclined ring model to
the disk spine suggests that the disk may be highly eccentric ($e\gtrsim0.16$).
A comparison of the disk flux with the stellar flux in each band suggests a
blue color that also does not significantly vary across the disk. We discuss
these results in terms of possible sources of asymmetry, where we find that
dynamical interaction with the planet companion, HD 106906b, is a likely
candidate.
