  Control of the spatial and temporal properties of light propagating in
disordered media have been demonstrated over the last decade using spatial
light modulators. Most of the previous studies demonstrated spatial focusing to
the speckle grain size, and manipulation of the temporal properties of the
achieved focus. In this work, we demonstrate temporal control of the total
impulse response integrated over all the spatial and polarization modes
propagating through a multimode fiber. We notably demonstrate a global
enhancement of light intensity at a chosen arrival time, as well as attenuating
light intensity at an arbitrary delay. We also demonstrate the full
polarization control of such engineered states and a multiple control at
different delay times, which opens interesting perspectives for non-linear
imaging through complex systems and high power fiber lasers.
