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Updated: May 15, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
PHIP sequences and dipolar fields I - single spin control
Martin C Korzeczek1, Ilai Schwartz2, Martin B Plenio1
1Institut für Theoretische Physik & IQST, Albert-Einstein Allee 11, Universität Ulm, D-89081 Ulm, Germany.
Summary
This study introduces new control sequences for parahydrogen induced polarization (PHIP) to overcome signal loss caused by magnetic field variations and sample magnetization effects in NMR.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Quantum Control
Background:
- Parahydrogen induced polarization (PHIP) enhances NMR signals by transferring spin order.
- B0/B1 field inhomogeneities and sample dipolar fields reduce PHIP efficiency in practical settings.
Purpose of the Study:
- To develop theoretical and practical methods to counteract detrimental effects in PHIP.
- To design and analyze control sequences for robust hyperpolarization.
Main Methods:
- Utilized average Hamiltonian theory and numerical simulations.
- Developed and characterized pulsed and continuous-wave (CW) control sequences.
- Investigated dipolar-field adjusted and suppressing protocols.
Main Results:
- Identified sequences that mitigate B0/B1 inhomogeneities and dipolar field effects.
- Discovered conditions where dipolar interactions can unexpectedly stabilize polarization transfer.
- Demonstrated practical guidance for designing PHIP sequences under experimental constraints.
Conclusions:
- The developed methods enable robust hyperpolarization in concentrated liquid-state NMR.
- Offers practical strategies for optimizing PHIP experiments in challenging conditions.
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