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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Time correlation functions via forward-backward quantum dynamics using Hamilton's law of varying action
1Department of Chemistry, University of Illinois, 601 S. Goodwin Avenue, Urbana, Illinois 61801, USA.
The Journal of Chemical Physics
|October 2, 2009
Summary
This study presents a new numerical method for calculating quantum trajectories using Bohm's equations. The approach accurately computes time correlation functions in complex quantum systems.
Area of Science:
- Quantum dynamics
- Computational chemistry
- Theoretical physics
Background:
- Calculating time correlation functions is crucial for understanding quantum systems.
- Existing methods for quantum dynamics can be computationally intensive or unstable.
- The forward-backward quantum dynamics (FBQD) formulation offers an alternative approach.
Purpose of the Study:
- To develop a stable numerical procedure for solving Bohm's equations of motion.
- To compute quantum trajectories within the FBQD framework.
- To accurately determine zero-temperature time correlation functions.
Main Methods:
- A novel numerical procedure based on a series expansion of the quantum trajectory.
- Exploiting Hamilton's law of varying action to determine expansion coefficients.
- Solving Bohm's equations of motion for quantum trajectory computation.
Main Results:
- The proposed method provides a stable numerical procedure.
- Accurate computation of quantum trajectories is achieved.
- Reliable determination of time correlation functions in anharmonic systems is demonstrated.
Conclusions:
- The new method enables accurate calculation of time correlation functions.
- The procedure is effective for strongly anharmonic bound systems.
- This approach offers a robust tool for quantum dynamics simulations.
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