A Novel Time-Resolved mid-IR Setup for the Investigation of Vibrational Dynamics in Aqueous Nanoclusters

Werhahn, J. C.; Bradler, M.; Hutzler, Daniel; Fuhrmann, S.; Riedle, Eberhard ; Iglev, Hristo und Kienberger, Reinhard (2013): A Novel Time-Resolved mid-IR Setup for the Investigation of Vibrational Dynamics in Aqueous Nanoclusters. In: Optics InfoBase Conference Papers: S. 12

Abstract

The ultrafast dynamics of the hydrogen bond network of liquid water remain a challenging field of research relevant to a plethora of disciplines, ranging from biology to geology. We present first results obtained with a newly developed optical setup, that allows mid-IR pump probe spectroscopy with a time resolution of 150 fs. The infrared pulses are generated via a recently proposed hybrid NOPA layout [1]. In order to achieve a selective excitation of the vibrational modes under investigation, the pump pulses are tunable in the range from 2000 to 4000 cm-1, and their spectral widths are controlled by a spectral grating selector. The pulses generated in this way have a spectral bandwidth between 20 and 150 cm−1 and pulse durations between 120 and 600 fs, with typical pulse energies of 3 μJ. The probe pulses are shorter than 50 fs (FWHM up to 600 cm−1), yielding few-cycle mid-IR pulses with unprecedented spectral width. The Fourier limit for these pulses is below 30 fs. Fig. 1(a) shows a typical FROG measurement of the probe pulses. They are spectrally resolved to obtain both temporal and spectral information on the fast processes under investigation.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• Sprache: Englisch