High extinction amplitude modulation in ultrashort pulse shaping

TL;DR

This paper investigates the balance between resolution and extinction in UV femtosecond pulse shaping, demonstrating a configuration that achieves high-resolution spectral filtering with high extinction using standard components.

Contribution

It provides a practical setup for high-resolution, high-extinction UV spectral filtering using standard optical components, optimizing the trade-offs involved.

Findings

Achieved 100 GHz filtering resolution in UV-A range.

Demonstrated high extinction spectral filtering with standard components.

Optimized component configuration for best spectral filtering performance.

Abstract

We explored the issues related to the resolution and the modulation extinction when filtering the spectrum of a UV femtosecond laser with a standard ultrashort pulse shaper. We have learned that a higher pulse shaping resolution often requires a larger working beam size or a higher density grating for greater dispersion. However, these approaches also introduce more optical errors and degrade the extinction. In this work, we examined specifics of each component to determine the best configuration of our spectral filtering setup. As a proof-of-concept demonstration, we utilized elements available as standard products and achieved 100 GHz filtering resolution with high extinction at the UV-A wavelength, which is superb in this wavelength range. The high extinction spectral filtering is especially important while modifying a broadband laser for the optical control of molecule's internal state.