Related Experiment Video
Updated: Jun 3, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum control by means of hamiltonian structure manipulation
A Donovan1, V Beltrani, H Rabitz
1Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
Physical Chemistry Chemical Physics : PCCP
|March 25, 2011
Summary
This study explores controlling quantum systems by manipulating their Hamiltonian structure, not just external fields. Researchers found that optimizing this structure allows for arbitrary quantum control without suboptimal traps.
Area of Science:
- Quantum control
- Quantum information science
- Atomic and molecular physics
Background:
- Traditional quantum optimal control focuses on time-dependent fields.
- A more general approach involves manipulating the system's Hamiltonian structure.
- This work inverts the typical control perspective.
Purpose of the Study:
- To investigate controlling quantum systems by optimizing their Hamiltonian structure.
- To analyze the control landscape defined by Hamiltonian structure and observable.
- To prove system controllability and explore landscape properties.
Main Methods:
- Defining control variables as system energies and transition dipole matrix elements.
- Analyzing the observable as a function of the Hamiltonian structure.
- Proving controllability and conducting numerical simulations on model systems.
Main Results:
- Demonstrated that a suitable Hamiltonian structure can yield arbitrary unitary transformations.
- Showed no suboptimal traps exist in the Hamiltonian structure control landscape for controllable systems.
- Found search effort to be invariant to system dimension and explored control mechanisms.
Conclusions:
- The study provides a foundation for laboratory implementation of Hamiltonian structure manipulation for optimal quantum control.
- This approach is particularly relevant when electromagnetic resources are limited.
- Unconstrained Hamiltonian structure optimization guarantees reaching the optimal control performance.
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