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Time-dependent pseudo Jahn-Teller effect: phonon-mediated long-time nonadiabatic relaxation
Taavi Vaikjärv1, Vladimir Hizhnyakov1
1Institute of Physics, University of Tartu, Riia 142, 51014 Tartu, Estonia.
The Journal of Chemical Physics
|February 18, 2014
Summary
This study examines impurity centers in solids, focusing on their quantum mechanical time evolution in excited electronic states. It details how phonon interactions influence these dynamics, providing insights into material properties.
Area of Science:
- Solid-state physics
- Quantum mechanics
- Materials science
Background:
- Impurity centers in solids exhibit complex electronic and vibrational behaviors.
- Understanding non-adiabatic effects and phonon interactions is crucial for characterizing excited states.
Purpose of the Study:
- To theoretically investigate the time evolution of impurity centers in quasi-degenerate electronic states.
- To analyze the influence of phonon emission on the dynamics of excited states.
Main Methods:
- Utilizing a strict quantum mechanical treatment for non-adiabatic effects.
- Employing a master equation to describe the dynamics of the excited state.
- Accounting for both the primary vibronic interaction and the phonon continuum.
Main Results:
- Calculations demonstrate the long-time evolution of impurity center vibrations.
- The study quantifies the impact of phonon emission to the bulk on these vibrations.
Conclusions:
- The theoretical framework accurately describes the dynamics of excited impurity centers.
- Phonon emission significantly influences the vibrational relaxation and long-time behavior of these systems.
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