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Updated: May 29, 2025
10:54
Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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Optimal control design strategies for pulsed dynamic nuclear polarization.
José P Carvalho1, David L Goodwin1, Nino Wili1
1Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
The Journal of Chemical Physics
|February 4, 2025
Summary
We developed new optimal control methods for pulsed dynamic nuclear polarization (DNP) sequences. These techniques enhance DNP experiment performance by optimizing pulse sequences for better polarization transfer.
Area of Science:
- Magnetic Resonance Spectroscopy
- Quantum Control Theory
Background:
- Dynamic Nuclear Polarization (DNP) enhances NMR signal sensitivity.
- Optimizing DNP pulse sequences is crucial for efficient polarization transfer.
- Existing optimal control methods face limitations in adaptability and performance.
Purpose of the Study:
- To present novel optimal control methods for periodic pulsed DNP sequences.
- To optimize a basic, repeatable pulse sequence element for improved performance and adaptability.
- To address limitations in current DNP pulse design strategies.
Main Methods:
- Utilizing matrix power and matrix logarithm functions.
- Employing an auxiliary matrix formalism.
- Deriving expressions for Gradient Ascent Pulse Engineering (GRAPE) optimization.
Main Results:
- Demonstrated effective and intuitive control of DNP experiments.
- Showcased adaptability to spin systems with varying coupling interaction sizes.
- Achieved enhanced performance through tailored effective Hamiltonians.
Conclusions:
- The presented optimal control methods offer a robust approach to DNP sequence optimization.
- These methods provide improved control over polarization transfer, overcoming existing limitations.
- The developed techniques are beneficial for a wide range of DNP applications.
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