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A hybrid local/global optimal control algorithm for dissipative systems with time-dependent targets: formulation and
Stephanie Beyvers1, Peter Saalfrank
1Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Str 24-25, Potsdam-Golm, Germany.
The Journal of Chemical Physics
|February 27, 2008
Summary
This study introduces a novel quantum optimal control algorithm combining global and local strategies for optical control of quantum systems. It enables precise manipulation of quantum dynamics, achieving targets like population inversion and wavepacket creation.
Area of Science:
- Quantum Control
- Physical Chemistry
- Spectroscopy
Background:
- Open-system quantum dynamics are crucial for understanding molecular processes.
- Controlling quantum systems requires sophisticated theoretical frameworks.
- Dissipative environments pose challenges for precise quantum state manipulation.
Purpose of the Study:
- To develop and test a novel quantum optimal control algorithm for time-dependent targets.
- To combine global and local control strategies for enhanced optimization.
- To apply the algorithm to realistic molecular systems, such as CO on a metal surface.
Main Methods:
- Open-system quantum optimal control theory applied to time-dependent operators.
- A novel algorithm combining global and local control strategies with time slicing.
- Iterative forward-backward propagation within subintervals and boundary condition matching.
- Representation of operators in the eigenstate basis of the field-free Hamiltonian.
Main Results:
- Demonstrated computational performance for a two-level system with relaxation.
- Successful extension to a many-level model representing CO on Cu(100).
- Achieved specific quantum control targets: population inversion, wavepacket creation, and overtone excitation.
Conclusions:
- The developed algorithm effectively controls quantum system dynamics in the presence of dissipation.
- The combined global-local strategy offers a powerful approach for complex quantum control tasks.
- The method is applicable to realistic molecular systems for spectroscopic applications.
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