Generation of picosecond pulses with variable temporal profiles and linear polarization by coherent pulse stacking in a birefringent crystal shaper

TL;DR

This paper presents a novel laser pulse shaping system using birefringent crystals to generate linearly polarized picosecond pulses with customizable temporal profiles, achieving high transmittance and stability.

Contribution

It introduces a new crystal configuration for pulse shaping that allows variable profiles with improved stability and a simplified double-pass setup reducing crystal count.

Findings

Achieved high transmittance and stability in shaped pulses.

Demonstrated generation of various temporal profiles including symmetric and asymmetric shapes.

Proposed a practical double-pass configuration reducing crystal usage.

Abstract

We report the study and demonstration of a new laser pulse shaping system capable of generating linearly polarized picosecond laser pulses with variable temporal profiles including symmetric intensity distributions such as parabolic, flattop, elliptical, triangular, as well as non-symmetric distributions, which are highly desired by various applications. It is found that both high transmittance and high stability of the shaped pulse can be achieved simultaneously when crystals are set at a specific phase delay through fine control of the crystal temperature. Although multi-crystal pulse stacking with different configurations were reported before particularly for flattop pulse generation, this new configuration leads to new opportunities for many potential applications over a wide range of laser wavelengths, pulse repetition rate, time structures and power levels. A practical double-pass temporal shaping configuration that significantly reduces the number of crystals is also proposed in this paper as a result of this work.