Advanced Data Processing of THz-Time Domain Spectroscopy Data with Sinusoidally Moving Delay Lines

TL;DR

This paper analyzes the data acquisition process in THz-time domain spectroscopy using oscillating delay lines, highlighting pitfalls, and introduces an open-source tool to improve data quality and reproducibility.

Contribution

It provides a detailed analysis of data handling pitfalls in THz spectroscopy with moving delay lines and offers a new open-source software for optimized data processing.

Findings

Proper data handling significantly improves dynamic range and SNR.

The open-source program 'parrot' facilitates better data analysis and reproducibility.

Avoiding common pitfalls enhances the quality of THz spectroscopy measurements.

Abstract

We provide a comprehensive technical analysis of the data acquisition process with oscillating delay lines for Terahertz-time domain spectroscopy. The utilization of these rapid stages, particularly in high-repetition-rate systems, is known to enable an effective reduction of noise content through averaging. However, caution must be exercised to optimize the data averaging process, with the goal of significantly optimizing the dynamic range (DR) and signal-to-noise ratio (SNR). Here we discuss some pitfalls to avoid and the effect of improper data handling on the dynamic range obtainable. A free and open-source program, called parrot (Processing All Rapidly & Reliably Obtained THz-traces), is provided alongside this publication to overcome the discussed pitfalls and facilitate the acceleration of experimental setups and data analysis, thereby enhancing signal fidelity and reproducibility.