  Exciton-polaritons are quasi-particles arising from the strong coupling
regime between excitons and photons. In planar microcavitites, phenomena such
as superfluidity or Bose-Einstein condensation can be observed. Those systems
have demonstrated to be very efficient in the hydrodynamic generation of
topological excitations, such as vortex-antivortex pairs or dark solitons.
However, the lifetime and motion of those excitations were limited by the
driven dissipative nature of the system. In this thesis, we present a rich
variety of results about the generation and control of such topological
excitations. Taking advantage of the optical bistability present in our system,
we were able to greatly enhanced the propagation length of vortices and
solitons generated in the wake of a structural defect, revealing in the mean
time an unexpected binding mechanism of the solitons which propagate parallel.
This behaviour was recovered in a specifically designed experiment, where we
artificially imprint dark soliton pairs on demand on a polariton superfluid.
The adaptability of our technique allowed for a detailed study of this
phenomenon, that we directly connected to the driven-dissipative nature of our
system. Finally, confined dark solitons were generated within guided intensity
channels on a static polariton fluid. The absence of flow lead to the
development of transverse snake instabilities of which we studied the
interesting properties.
