Coherent two-dimensional ultraviolet spectroscopy in fully noncollinear geometry.

Area of Science:

• Spectroscopy
• Ultrafast Science
• Physical Chemistry

Background:

• Coherent two-dimensional (2D) spectroscopy is a powerful technique for probing molecular dynamics.
• Existing setups often face limitations in terms of size, complexity, and spectral range.
• Ultraviolet (UV) spectroscopy offers unique insights into electronic transitions of many molecules.

Purpose of the Study:

• To introduce a novel, fully noncollinear coherent 2D spectroscopy setup operating in the UV domain.
• To demonstrate a miniaturized and all-reflective optical design for enhanced stability and versatility.
• To validate the setup's performance through phase stability measurements and spectral acquisition.

Main Methods:

• Development of a miniaturized, all-reflective optical system for UV spectroscopy.
• Implementation of pairwise beam manipulation for achieving robust phase stability.
• Optimization of the setup for the 250–375 nm wavelength range.
• Acquisition of 2D spectra using 50 fs pulses at 287 nm.

Main Results:

• Successful implementation of fully noncollinear coherent 2D spectroscopy in the UV.
• Demonstrated phase stability over several hours via interferometric measurements.
• Obtained 2D spectra of the UV chromophore p-terphenyl in ethanol.
• The developed technique is transferable to other wavelength regimes.

Conclusions:

• The novel UV 2D spectroscopy setup offers a stable and compact platform for molecular dynamics studies.
• This technique provides a new avenue for investigating electronic structures and dynamics in the UV spectral region.
• The design's versatility allows for adaptation to various spectroscopic applications and wavelength ranges.