  The complex temporal behavior of an ultrashort pulse of light propagating
through a multiply scattering medium can be characterized experimentally
through a time-gated transmission matrix. Using a spatial light modulator, we
demonstrate here, that injecting singular vectors of this matrix allows us to
optimally control energy deposition at any controllable delay time. Our
approach provides insights into fundamental aspects of multi-spectral light
scattering and could find applications in imaging or coherent control.
