title: High fidelity femtosecond pulses from an ultrafast fiber laser system via adaptive amplitude and phase pre-shaping.
abstract: The generation of high-fidelity femtosecond pulses is experimentally demonstrated in a fiber based chirped-pulse amplification (CPA) system through an adaptive amplitude and phase pre-shaping technique. A pulse shaper, based on a dual-layer liquid crystal spatial light modulator (LC-SLM), was implemented in the fiber CPA system for amplitude and phase shaping prior to amplification. The LC-SLM was controlled using a differential evolution algorithm, to maximize a two-photon absorption detector signal from the compressed fiber CPA output pulses. It is shown that this approach compensates for both accumulated phase from material dispersion and nonlinear phase modulation. A train of pulses was produced with an average power of 12.6W at a 50MHz repetition rate from our fiber CPA system, which were compressible to high fidelity pulses with a duration of 170 fs.
authors.affiliation: Optoelectronics Research Centre, University of Southampton, Southampton, UK.
authors.forename: Jerry
authors.initials: J
authors.lastname: Prawiharjo
authors.forename: Nikita K
authors.initials: NK
authors.lastname: Daga
authors.forename: Rui
authors.initials: R
authors.lastname: Geng
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Price
authors.forename: David C
authors.initials: DC
authors.lastname: Hanna
authors.forename: David J
authors.initials: DJ
authors.lastname: Richardson
authors.forename: David P
authors.initials: DP
authors.lastname: Shepherd
mesh_terms: D000669:Amplifiers, Electronic; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D007834:Lasers; D008962:Models, Theoretical; D009991:Oscillometry / Q000295:instrumentation*; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*