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ARL Spectral Fitting as an Application to Augment Spectral Data via Franck-Condon Lineshape Analysis and Color Analysis
Published on: August 19, 2021
Resonance lineshapes in two-dimensional Fourier transform spectroscopy.
Mark E Siemens1, Galan Moody, Hebin Li
1JILA, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440, USA.
Optics Express
|August 20, 2010
Summary
We developed an analytical model for resonance lineshapes in two-dimensional Fourier transform spectroscopy. This method accurately quantifies spectral broadening in complex experimental data.
Area of Science:
- Spectroscopy
- Quantum Optics
- Physical Chemistry
Background:
- Two-dimensional Fourier transform spectroscopy (2D FTIR) is a powerful technique for analyzing molecular dynamics.
- Understanding resonance lineshapes is crucial for interpreting complex spectral data.
- Existing models often struggle with arbitrary spectral inhomogeneity.
Purpose of the Study:
- To derive an analytical lineshape function for 2D FTIR.
- To provide a method for quantitative analysis of spectral broadening.
- To enable accurate characterization of homogeneous and inhomogeneous broadening.
Main Methods:
- Solving optical Bloch equations for a two-level system in the 2D time domain.
- Applying the projection-slice theorem of 2D Fourier transforms.
- Developing an analytical form for resonance lineshapes.
Main Results:
- An analytical expression for resonance lineshapes in 2D FTIR was derived.
- The model accurately describes diagonal and cross-diagonal slices in 2D frequency data.
- The derived form accounts for arbitrary spectral inhomogeneity.
Conclusions:
- The analytical lineshape model provides a robust framework for 2D FTIR data analysis.
- This approach enables precise quantitative measurements of spectral broadening.
- The findings advance the application of 2D FTIR in various scientific fields.
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