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Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Communication: Induced photoemission from nonadiabatic dynamics assisted by dynamical Stark effect
Yasuki Arasaki1, Simona Scheit, Kazuo Takatsuka
1Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Tokyo, Japan.
The Journal of Chemical Physics
|May 3, 2013
Summary
Electron transfer couples vibrational dynamics between ionic and covalent surfaces, leading to photon emission. This process, controllable by external fields, offers a new way to study ultrafast molecular dynamics.
Area of Science:
- Quantum dynamics
- Molecular physics
- Spectroscopy
Background:
- Nonadiabatic interactions couple vibrational dynamics on ionic (large dipole) and covalent (small dipole) potential energy surfaces.
- Electron transfer can induce long-range electron jumps, causing sudden changes in molecular dipole moments.
Purpose of the Study:
- To investigate the possibility of photon emission resulting from coupled vibrational dynamics and electron transfer.
- To explore the control of this photoemission using external fields.
- To establish a novel method for studying ultrafast molecular dynamics.
Main Methods:
- Coupled quantum wavepacket dynamics calculations were employed.
- Simulations analyzed the influence of external fields on the photoemission process.
Main Results:
- Photon emission was demonstrated to occur under the described conditions.
- The photoemission process was shown to be controllable by an external field.
- The study confirmed the link between electron transfer, dipole moment changes, and photon emission.
Conclusions:
- The proposed photoemission mechanism is viable and controllable.
- This phenomenon provides an alternative pathway for investigating femtosecond and subfemtosecond vibrational and electronic dynamics.
- The findings suggest potential applications as a unique optical source for ultrafast spectroscopy.
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