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Updated: Jul 11, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Probing coherence aspects of adiabatic quantum computation and control
1Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India.
The Journal of Chemical Physics
|October 2, 2007
Summary
Robust quantum control is achieved by using quantum interference to cancel unwanted pathways, minimizing decoherence. A new method quantifies two-level character in quantum systems by tracking coherent evolution via off-diagonal density matrix elements.
Area of Science:
- Quantum mechanics
- Quantum information science
- Atomic physics
Background:
- Quantum interference offers pathways to control quantum systems.
- Decoherence remains a significant challenge in maintaining quantum states.
- Adiabatic coherent control is a promising technique for quantum manipulation.
Purpose of the Study:
- To propose a method for quantifying the two-level character in multilevel quantum systems.
- To demonstrate how quantum interference can control decoherence.
- To explain counterintuitive results in quantum excitation processes.
Main Methods:
- Utilizing quantum interference to cancel couplings to nonradiative channels.
- Applying adiabatic coherent control approaches.
- Quantifying two-level character through the evolution of off-diagonal density matrix elements.
Main Results:
- Quantum interference effectively controls decoherence by canceling unwanted excitation pathways.
- A novel quantification of two-level character is proposed.
- The coherent character transitions from real to imaginary under adiabatic conditions, indicating distinct population dynamics.
Conclusions:
- Adiabatic coherent control provides robust control over decoherence.
- The proposed quantification method offers insights into the behavior of multilevel quantum systems.
- Understanding population exchange dynamics is crucial for controlling quantum excitation processes.
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