Open AccessGeneration of flat-top picosecond pulses by coherent pulse stacking in a multicrystal birefringent filter
Author(s) -
I. Will,
G. Klemz
Publication year - 2008
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.16.014922
Subject(s) - optics , birefringence , polarizer , pulse shaping , pulse (music) , filter (signal processing) , ultrashort pulse , materials science , bandwidth limited pulse , femtosecond pulse shaping , liquid crystal tunable filter , picosecond , physics , laser , computer science , wavelength , detector , computer vision
This paper deals with the pulse-shaping properties of birefringent filters that feature an optical layout similar to a Solc fan filter. A simple computational model is given that explains the pulse-shaping process in the fan filter in two steps: First, the input pulse is split into several mutually delayed replicas due to the birefringence of the crystals. Second, these replicas interfere at the output polarizer of the filter and form the shaped output pulse. Fine-tuning of the phases of the replicas of the input pulse is permitted by tuning the temperature of the crystals. A birefringent pulse shaper containing ten birefringent crystals was investigated experimentally. The shape of the output pulses was measured by means of a special cross-correlation technique. Although a variety of pulse shapes can be generated with the described filter, it is particularly well suited for generation of flattop pulses featuring a 20-ps-long plateau and rising and falling edges shorter than 2 ps.