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Two-dimensional ultrafast fourier transform spectroscopy in the deep ultraviolet
Chien-hung Tseng1, Spiridoula Matsika, Thomas C Weinacht
1Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA.
Optics Express
|April 8, 2010
Summary
We developed deep ultraviolet two-dimensional ultrafast Fourier transform spectroscopy. This novel technique enables rapid scanning and high phase stability for studying molecules like the DNA nucleobase Adenine.
Area of Science:
- Spectroscopy
- Ultrafast Spectroscopy
- Chemical Physics
Background:
- Two-dimensional ultrafast Fourier transform spectroscopy (2D-UFTS) is a powerful technique for studying molecular dynamics.
- Previous limitations in deep ultraviolet (DUV) spectroscopy hindered its application in studying molecules like DNA bases.
- Advancements in pulse shaping technology are crucial for extending spectroscopic capabilities to shorter wavelengths.
Purpose of the Study:
- To demonstrate a novel 2D-UFTS technique operating in the deep ultraviolet (DUV) spectral region (~260 nm).
- To overcome the technical challenges associated with performing ultrafast spectroscopy in the DUV.
- To apply this new method for investigating the photophysical properties of the DNA nucleobase Adenine.
Main Methods:
- Implementation of an acousto-optic modulator-based pulse shaper for DUV light.
- Development of a DUV 2D-UFTS setup enabling rapid scanning capabilities.
- Achieving high phase (time) stability (approximately 0.017 rad) and phase cycling for enhanced signal-to-noise ratio.
Main Results:
- Successful demonstration of 2D-UFTS in the deep ultraviolet spectral range.
- Attainment of rapid scanning and high phase stability, crucial for time-resolved measurements.
- Acquisition of 2D-UFTS spectra of the DNA nucleobase Adenine, providing insights into its excited-state dynamics.
Conclusions:
- The developed DUV 2D-UFTS technique is a significant advancement for studying molecules in this spectral region.
- This method offers improved temporal resolution and stability compared to previous approaches.
- The study provides a new spectroscopic tool for investigating fundamental photochemistry and photophysics of biologically relevant molecules.
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