Modifications of filament spectra by shaped octave-spanning laser pulses

Abstract

In this paper we examine the spectral changes in a white light laser filament due to different pulse shapes generated by a pulse shaping setup. We particularly explore how the properties of the filament spectra can be controlled by parametrically tailored white light pulses. The experiments are carried out in a gas cell with up to 9 bar of argon. Plasma generation and self-phase modulation strongly affect the pulse in the spectral and temporal domain. By exploiting these effects we show that the pulse spectrum can be modified in a desired way by either using second order parametric chirp functions to shift the filament spectrum to higher or lower wavelengths, or by optimizing pulse shapes with a genetic algorithm to generate more complex filament spectra. This paper is one of the first examples of the application of complex, parametrically shaped white light pulses.

Multichromatic Polarization-Controlled Pulse Sequences for Coherent Control of Multiphoton Ionization

“…Advanced techniques for generating tailored ultrashort laser pulses on the one hand and for highly differential detection on the other hand, have been key to experimental advances in coherent control. Since the implementation of the first single layer 128 pixel pulse shaping devices [30][31][32][33][34][35][36][37][38][39][40], remarkable advances have been achieved towards high precision pulse shaping using 640 pixel devices [41][42][43][44][45][46][47][48][49][50] and polarization shapers [51,52], vector-field synthesizers [53][54][55][56][57][58] and supercontinuum pulse shaping [59][60][61][62][63][64][65][66]. Recently, we have introduced a scheme for polarization shaping of carrier-envelope phase (CEP)-stable over-octave-spanning white light supercontinua (WLS) to generate polarizationtailored bichromatic fields [65].…”