High sensitivity transient infrared spectroscopy: a UV/Visible transient grating spectrometer with a heterodyne detected infrared probe

Abstract

We describe here a high sensitivity means of performing time resolved UV/Visible pump, infrared probe spectroscopy using optically Heterodyne Detected UV-IR Transient Gratings. The experiment design employed is simple, robust and includes a novel means of generating phase locked pulse pairs that relies on only mirrors and a beamsplitter. A signal to noise ratio increase of 24 compared with a conventional pump-probe arrangement is demonstrated. Winterthurerstrasse 190, Switzerland *phamm@pci.uzh.ch Abstract: We describe here a high sensitivity means of performing time resolved UV/Visible pump, infrared probe spectroscopy using optically Heterodyne Detected UV-IR Transient Gratings. The experiment design employed is simple, robust and includes a novel means of generating phase locked pulse pairs that relies on only mirrors and a beamsplitter. A signal to noise ratio increase of 24 compared with a conventional pump-probe arrangement is demonstrated.

Applications of two-dimensional infrared spectroscopy

“…[9][10][11][12][13][14][15][16][17][18] For instance, transient 2D IR spectroscopy is possible when combined with laser-induced temperature jump, photo-induced isomerization, or rapid mixing to initiate chemical reactions. 10,71,76,[81][82][83]129 Multidimensional experiments involving a combination of visible and IR excitation beams also have been reported, 130,131 providing information about vibronic coupling that promises to be particularly powerful for advancing our understanding of photosynthetic systems. Frequency-domain versions of 2D IR and visible-IR nonlinear experiments based on Raman processes, which employ narrow band, tunable excitation pulses, have also been well developed and applied in a variety of studies, for example in both nanomaterial and proteomic research.…”

Two-dimensional electronic–vibrational spectroscopy: Exploring the interplay of electrons and nuclei in excited state molecular dynamics

“…This severely limits the practical experimental geometries by which this type of spectroscopy can be performed in order to obtain a background-free signal. 21 Rather, the implementation of phase cycling with a pump-probe geometry (k 1 = k 2 ≠ k 3 ) is the most useful means for isolating the 2DEV signal. In the pump-probe geometry, the third-order signal intensity is given by…”

Recent advances in multidimensional ultrafast spectroscopy

“…The partially collinear, or pump–probe, geometry ( figure 3 b ) removes the problem of phase matching in experiments where very different pump and probe frequencies are used [ 89 ], and greatly reduces the complexity of the alignment procedures and experimental design, as only two beam paths are required. 2D signals in the partially collinear geometry are emitted collinearly with k 3 ( k s = ± k 1 ∓ k 2 + k 3 ), which acts so as to ‘self-heterodyne’ the signal, with the consequence that the k 3 – k sig phase relationship is known, and 2D spectra are automatically phased [ 74 , 90 , 91 ].…”