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Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Molecular-alignment-assisted high-energy supercontinuum pulse generation in air
1State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.
Optics Letters
|July 29, 2010
Summary
We achieved controllable generation of high-energy supercontinuum pulses using femtosecond filamentation in aligned diatomic molecules. This method suppresses multifilamentation and reduces ionization loss for efficient supercontinuum generation.
Area of Science:
- Nonlinear Optics
- Laser Physics
- Quantum Optics
Background:
- Supercontinuum generation is crucial for various applications, but high-energy generation often suffers from multifilamentation and ionization losses.
- Femtosecond filamentation in gases is a known method for generating broad optical spectra.
Purpose of the Study:
- To demonstrate controllable generation of high-energy supercontinuum pulses.
- To investigate the role of molecular alignment in femtosecond filamentation for supercontinuum generation.
- To suppress multifilamentation and reduce ionization losses in high-energy supercontinuum generation.
Main Methods:
- Utilizing high-energy femtosecond laser pulses with linear polarization.
- Employing prealigned diatomic molecules in air to control filamentation.
- Investigating the cross-defocusing effect induced by perpendicularly oriented molecules.
Main Results:
- Achieved controllable generation of a high-energy supercontinuum pulse (1.8 mJ).
- Demonstrated suppressed multifilamentation compared to standard filamentation.
- Observed decreased multiphoton ionization loss due to reduced ionization probability.
Conclusions:
- Prealigned diatomic molecules enable controllable, high-energy supercontinuum generation.
- The cross-defocusing effect in aligned molecules is key to suppressing unwanted nonlinear effects.
- This technique offers a promising pathway for efficient high-energy light source development.
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