A 100 kHz Pulse Shaping 2D-IR Spectrometer Based on Dual Yb:KGW Amplifiers

Abstract

A high-speed, high-sensitivity and compact two-dimensional infrared (2D-IR) spectrometer based on 100 kHz Yb:KGW regenerative amplifier technology is described and demonstrated. The setup is three color, using an independent pump OPA and two separately tunable probe OPAs. The spectrometer uses 100 kHz acousto-optic pulse shaping on the pump beam for rapid 2D-IR acquisitions. The shot-to-shot stability of the laser system yields excellent signal-to-noise figures (∼10 μOD noise on 5000 laser shots). We show that the reduced bandwidth of the Yb:KGW amplifiers in comparison with conventional Ti:sapphire systems does not compromise the ability of the setup to generate high-quality 2D-IR data. Instrument responses of <300 fs are demonstrated and 2D-IR data presented for several systems of interest to physical chemists, showing spectral diffusion in NaSCN, amide I and II bands of a β sheet protein and DNA base-pair-backbone couplings. Overall, the increased data acquisition speed, intrinsic stability, and robustness of the Yb:KGW lasers are a significant step forward for 2D-IR spectroscopy.

Photon echoes and two dimensional spectra of the amide I band of proteins measured by femtosecond IR – Raman spectroscopy

“…† Experiments for generating and detecting IR-Raman signals using the pulse sequences in Fig. 2b-d were built via access to the LIFEtime 37,38 and Ultra A 39 lasers of the UK Central Laser Facility. Detailed descriptions of these experiments are found in ESI Section 2.…”

Investigating Electron-Phonon Coupling in Formamidinium Lead Iodide Perovskite Using Ultrafast Laser Spectroscopy

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An Ultrafast Vibrational Study of Dynamical Heterogeneity in the Protic Ionic Liquid Ethyl-Ammonium Nitrate

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