Tracing, amplifying, and steering chromophore-bath coherences by ultrashort pulse trains.
With a train of 5 phase controlled ultrashort pulses, we enhance a coherent vibronic transition to exceed a dominant incoherent background. The interference in the chromophore generates a spectral comb which is adjusted to a progression of internal Br2 vibrations coupled to phonons of the surrounding Ar lattice. It steers the mode-specific phase evolution of the system. The trains are generated by straightforward programing of the spectral comb in a pulse shaper unit. Excitations involving several hundred degrees of freedom remain coherent on a picosecond time scale.
Ibrahim
Heide
H
Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany.
Héjjas
Mónika
M
Schwentner
Nikolaus
N