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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Selective Enhancement of Spectroscopic Features by Quantum Optimal Control
Daniel Keefer1, Shaul Mukamel1
1Departments of Chemistry and Physics and Astronomy, University of California, Irvine, California 92697-2025, USA.
Physical Review Letters
|May 7, 2021
Summary
Researchers used optimal control theory (OCT) to amplify spectroscopic signals by optimizing the signal directly, not the molecular wave function. This method enhances weak coherence signals for better detection in quantum pathway steering.
Area of Science:
- Quantum dynamics
- Spectroscopy
- Physical chemistry
Background:
- Optimal control theory (OCT) typically targets unobservable molecular wave functions.
- Steering atomic motions requires precise control over quantum pathways.
- Spectroscopic signals often contain weak coherence-based signatures.
Purpose of the Study:
- To develop and simulate a method using OCT to optimize observable spectroscopic signals directly.
- To enhance the detection of weak coherence signals in molecular dynamics.
- To demonstrate temporal control and amplification of specific spectroscopic signals.
Main Methods:
- Simulations employing optimal control theory (OCT).
- Shaping optical pump pulses to control x-ray stimulated Raman signals.
- Focusing on signals generated during passage through conical intersections.
Main Results:
- Spectroscopic signal optimization directly through OCT simulations.
- Temporal control and amplification of x-ray stimulated Raman signals by up to 2 orders of magnitude.
- Demonstrated enhancement of weak coherence-based signatures.
Conclusions:
- Optimizing spectroscopic signals directly is a viable approach in OCT.
- This method significantly enhances the detectability of subtle quantum phenomena.
- The approach is broadly applicable to signals dependent on positive definite operator expectation values.
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