Group-velocity control by quadratic nonlinear interactions.
We give direct experimental evidence that the group velocity of ultrashort pulses can be controlled through chi(2)-cascaded interactions, under the condition of large group-velocity mismatch. The group velocity can be finely tuned by acting on pulse intensity and phase mismatch. Group-delay shifts up to 50 fs are achieved by propagating 40 fs pulses around 1400 nm in a 25 mm long periodically poled stoichiometric lithium tantalate crystal.
Marangoni
Marco
M
Dipartimento di Fisica, Politecnico di Milano, ULTRAS-CNR-INFM, IFN-CNR, Piazza L. Da Vinci 32, I-20133 Milan, Italy. marco.marangoni@polimi.it
Manzoni
Cristian
C
Ramponi
Roberta
R
Cerullo
Giulio
G
Baronio
Fabio
F
De Angelis
Costantino
C
Kitamura
Kenji
K