Sub-two-cycle pulses by soliton self-compression in highly nonlinear photonic crystal fibers.
We demonstrate the direct generation of sub-two-cycle pulses by soliton self-compression of femtosecond pulses from a Ti:sapphire laser at 85 MHz using a 4.85-mm-long highly nonlinear photonic crystal fiber. Sub-nanojoule, 41 fs input pulses were compressed down to 4.6 fs without additional phase compensation schemes. To our knowledge, these are the shortest pulses obtained by soliton-effect compression of a laser oscillator. Efficient, near-dispersionless collimation of the fiber output was achieved with a simple lens and an octave-spanning double-chirped mirror pair. The full electric field of the compressed pulses was retrieved with a genetic algorithm applied to spectral and interferometric autocorrelation measurements, and the results are well described by numerical simulations.
Amorim
A A
AA
IFIMUP and IN-Instituto de Física dos Materiais da Universidade do Porto, Departamento de Física, Faculdade de Ciências, Universidade do Porto, R. do Campo Alegre 687,4169-007 Porto, Portugal.
Tognetti
M V
MV
Oliveira
P
P
Silva
J L
JL
Bernardo
L M
LM
Kärtner
F X
FX
Crespo
H M
HM