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Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
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Molecular memory effects in transient stimulated Raman scattering in the atmosphere
Applied Optics
|June 10, 2010
Summary
Molecular memory effects can enhance transient stimulated Raman scattering (TSRS) in atmospheric pulse trains. Enhancement is negligible for horizontal propagation with >0.1 ns spacing but depends on spacing, angle, and energy for upward propagation.
Area of Science:
- Optics and Photonics
- Atmospheric Physics
- Nonlinear Optics
Background:
- Transient stimulated Raman scattering (TSRS) is a key nonlinear optical process.
- Molecular memory effects describe how preceding molecular states influence subsequent interactions.
- Atmospheric propagation introduces complexities due to environmental variables.
Purpose of the Study:
- To investigate the enhancement of TSRS in atmospheric pulse trains.
- To analyze the influence of molecular memory effects on TSRS.
- To determine the conditions under which TSRS enhancement is significant during atmospheric propagation.
Main Methods:
- Theoretical analysis of TSRS considering molecular memory.
- Modeling of pulse train propagation through the atmosphere.
- Parametric studies varying interpulse spacing, zenith angle, and pulse energy density.
Main Results:
- For horizontal propagation, TSRS enhancement is negligible for interpulse spacing greater than 0.1 nanoseconds.
- For upward atmospheric propagation, TSRS enhancement is dependent on interpulse spacing.
- Enhancement is also shown to be a function of zenith angle and pulse energy density for upward propagation.
Conclusions:
- Molecular memory effects can significantly impact TSRS in atmospheric pulse trains under specific conditions.
- The orientation of propagation (horizontal vs. upward) critically affects the relevance of these memory effects.
- Optimizing pulse train parameters is crucial for harnessing or mitigating TSRS enhancement in atmospheric applications.
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