Molecular-alignment-assisted high-energy supercontinuum pulse generation in air.

We demonstrate controllable generation of a high-energy supercontinuum pulse of 1.8 mJ through femtosecond filamentation in prealigned diatomic molecules in air. For high-energy femtosecond laser pulses of linear polarization, the focusing condition is loosened by the cross-defocusing effect from the perpendicularly orientated molecules, which promotes the high-energy supercontinuum generation with suppressed multifilamentation and decreased multiphoton ionization loss due to the reduced ionization probability.