Researchers at the Laboratory of Lightwave Metrology and Attoworld have made significant advancements in molecular fingerprinting through the development of a standardized data processing technique for infrared field-resolved spectroscopy (FRS). This novel approach solves an importnt challenge of FRS, enabling more accurate and comparable measurements with different instruments – a crucial requirement for real-world applications.
FRS, which captures the molecular vibrations excited by ultra-short infrared pulses, offers superior sensitivity compared to traditional time-integrating spectroscopies like Fourier-transform infrared (FTIR) spectroscopy. One key advantage of FRS lies in its ability to analyse the molecular signal directly in the time domain and thereby to temporally separate the resonant molecular response from the noise carried by the excitation pulse. This results in cleaner, more sensitive measurements. However, the molecular signal’s dependence on the amplitude and phase of the excitation pulse has so far hindered the reproducibility and comparability of time-filtered FRS data.
The new paper reports on a data processing procedure that strongly mitigates these issues. The method effectively removes the technical noise linked to the excitation pulse, and, at the same time, rendering the molecular signal largely independent of the instrument-specific parameters. This procedure not only enhances the sensitivity and reproducibility of FRS but also facilitates its integration with established spectral processing techniques. As a result, FRS data can now be directly compared to existing FTIR data, expanding the potential applications of this technology in chemical, biological, and medical research.
This new approach represents a significant step toward the practical implementation of FRS in various analytical fields, providing a blueprint for standardized FRS data processing and paving the way for broader adoption of this powerful technique.
Original publication: M. Huber, M. Trubetskov, W. Schweinberger, P. Jacob, M. Zigman, F. Krausz, I. Pupeza, “Standardized electric-field-resolved molecular fingerprinting,” Analytical Chemistry 96, 13110 (2024)
https://pubs.acs.org/doi/full/10.1021/acs.analchem.4c01745