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Updated: Jun 7, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Molecular quantum control landscapes in von Neumann time-frequency phase space
Stefan Ruetzel1, Christoph Stolzenberger, Susanne Fechner
1Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
The Journal of Chemical Physics
|November 2, 2010
Summary
We introduce a novel time-frequency method using the von Neumann representation for ultrafast laser pulse shaping. This approach provides new insights into molecular dynamics and quantum control mechanisms.
Area of Science:
- Quantum Optics
- Physical Chemistry
- Spectroscopy
Background:
- The von Neumann representation offers a joint time-frequency description for ultrafast laser pulses.
- This representation was previously suggested as a basis for pulse shaping experiments.
Purpose of the Study:
- To utilize the von Neumann basis for representing multidimensional molecular control landscapes.
- To gain deeper insights into molecular dynamics through this representation.
- To demonstrate quantum control using tailored laser pulses.
Main Methods:
- Development of three time-frequency phase space scanning procedures based on the von Neumann formalism.
- Variation of intensity, time-frequency phase space position, and relative phase of subpulses.
- Characterization of shaped pulses using Fourier-transform spectral interferometry.
Main Results:
- Successful representation of molecular control landscapes in a time-frequency phase space.
- Demonstration of quantum control on the laser dye IR140.
- Elucidation of a time-frequency pump-dump mechanism.
Conclusions:
- The von Neumann representation is effective for analyzing and controlling molecular dynamics.
- Time-frequency pulse shaping offers a powerful tool for quantum control.
- This formalism provides a framework for understanding complex molecular interactions.
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