Widely tunable soliton frequency shifting of few-cycle laser pulses.
Photonic-crystal fibers are employed to demonstrate widely tunable frequency down-conversion of unamplified 6-fs Ti:sapphire laser pulses through the soliton self-frequency shift induced by the Raman effect. Wavelength shifts as large as 500 nm are achieved for input few-cycle pulses with broadband spectra centered at approximately 820 nm. The central wavelength of the redshifted output of a photonic-crystal fiber is smoothly tuned from the low-frequency edge in the spectrum of the 6-fs Ti:sapphire laser pulse up to 1.35 microm by varying the input energy in the fundamental mode of the fiber.
Ishii
N
N
Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.
Teisset
C Y
CY
Köhler
S
S
Serebryannikov
E E
EE
Fuji
T
T
Metzger
T
T
Krausz
F
F
Baltuska
A
A
Zheltikov
A M
AM