Live Magnetic Observation of Parahydrogen Hyperpolarization Dynamics

The entry contains numerical data files, processing code (Wolfram Mathematica) and simulation code (Wolfram Mathematica running the 'SpinDynamica' packages) to generate Figures 1 to 6 of the manuscript titled above, arXiv preprint: https://arxiv.org/abs/2402.10766. A PDF export of the Mathematica code is also provided.

Authors: James Eills, Morgan W. Mitchell, Irene Marco Rius, Michael C. D. Tayler

Abstract: Hyperpolarized nuclear spins in molecules exhibit high magnetization that is unachievable by classical polarization techniques, making them widely used as sensors in physics, chemistry, and medicine. The state of a hyperpolarized material, however, is typically only studied indirectly and with partial destruction of magnetization, due to the nature of conventional detection by resonant-pickup nuclear magnetic resonance spectroscopy or imaging. Here we establish atomic magnetometers with sub-pT sensitivity as an use an alternative modality to detect in real time the complex dynamics of hyperpolarized materials without disturbing or interrupting the magnetogenesis process.  As an example of dynamics that are impossible to detect in real time by conventional means, we examine parahydrogen-induced 1H and 13C magnetization during adiabatic eigenbasis transformations at μT-field avoided crossings.  Continuous but nondestructive magnetometry reveals previously unseen spin dynamics, fidelity limits, and magnetization back-action effects.  As a second example, we apply magnetometry to observe the chemical-exchange-driven 13C hyperpolarization of [1-13C]-pyruvate — the most important spin tracer for clinical metabolic imaging. The approach can be readily combined with other high-sensitivity magnetometers and is applicable to a broader range of general observation scenarios involving production, transport and systems interaction of hyperpolarized compounds.