Interaction of two parallel femtosecond filaments at different wavelengths in air.
We study the interaction of two parallel-launched femtosecond filaments at their fundamental-wave and second-harmonic frequencies in air. Besides the Kerr effect within the pulse duration, the impulsive alignment of the diatomic molecules in the fundamental-wave filament leads to controllable and field-free achievable attraction, fusion, or repulsion of the second-harmonic filament. The molecular-alignment-assisted filament interaction is further confirmed by the fluorescence intensity variation and spectral modulation of the second-harmonic filament at various molecular alignment revivals.
State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
Jian
J
Wu
Yuqi
Y
Tong
Xuan
X
Yang
Hua
H
Cai
Peifen
P
Lu
Haifeng
H
Pan
Heping
H
Zeng