Stimulated amplification of UV emission in a femtosecond filament using adaptive control

We report on experimental results in adaptive control over UV fluorescence from a femtosecond filament created in nitrogen. We demonstrate that an optimized sequence of femtosecond pulses can effectively align, selectively ionize and excite molecular nitrogen ions, resulting in stimulated amplification of a filament continuum seeded emission at 391 nm, 358 nm and 428 nm wavelengths.