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Updated: Jun 8, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Dynamic nuclear polarization pulse sequence engineering using single-spin vector effective Hamiltonians
A B Nielsen1, J P A Carvalho1, D L Goodwin1
1Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark. abn@chem.au.dk.
Physical Chemistry Chemical Physics : PCCP
|November 5, 2024
Summary
Pulsed Dynamic Nuclear Polarization (DNP) pulse sequences can be systematically designed using single-spin vector effective Hamiltonian theory. This approach enables enhanced nuclear spin polarization for improved detection sensitivity.
Area of Science:
- Magnetic Resonance Spectroscopy
- Physical Chemistry
Background:
- Dynamic Nuclear Polarization (DNP) enhances nuclear spin polarization by transferring electron spin polarization.
- Pulsed DNP is an emerging area, driven by advancements in arbitrary waveform generators.
- Systematic design of DNP pulse sequences is crucial for optimizing polarization transfer.
Purpose of the Study:
- To systematically design static-powder Dynamic Nuclear Polarization (DNP) pulse sequences.
- To explore the interplay between linear and bilinear terms in effective Hamiltonians for polarization transfer.
- To demonstrate a broadband DNP pulse sequence for enhanced sensitivity.
Main Methods:
- Utilized single-spin vector effective Hamiltonian theory for pulse sequence design.
- Analyzed two regimes: low microwave field amplitude and high-power regime.
- Employed numerical non-linear optimization combined with experimental validation.
Main Results:
- Validated the single-spin vector model with experimental DNP results at 9.8 GHz/15 MHz.
- Developed and demonstrated the PLATO pulse sequence for broadband DNP.
- Achieved an 80 MHz bandwidth with a peak microwave field amplitude of 32 MHz.
Conclusions:
- Single-spin vector effective Hamiltonian theory provides a robust framework for designing pulsed DNP sequences.
- The PLATO sequence offers significant bandwidth for enhanced polarization transfer.
- Pulsed DNP techniques are becoming increasingly viable for sensitive detection.
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