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Dipolar field effects in a solid-state NMR maser pumped by dynamic nuclear polarization
Vineeth Francis Thalakottoor Jose Chacko1, Daniel Abergel1
1Laboratoire des Biomolécules, LBM, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France. daniel.abergel@ens.psl.eu.
Physical Chemistry Chemical Physics : PCCP
|April 4, 2023
Summary
We observed a pulsed maser using hyperpolarized proton spins at cryogenic temperatures. Simulations using Bloch-Maxwell-Provotrov equations explain the maser
Area of Science:
- Quantum Electronics
- Solid-State Physics
- Magnetic Resonance
Background:
- Dynamic Nuclear Polarization (DNP) enables hyperpolarization of nuclear spins.
- Pulsed masers exhibit unconventional behavior, including multiple asymmetric pulses.
- Previous observations showed persistent maser activity with negatively polarized spins.
Purpose of the Study:
- To report and analyze observations of a pulsed solid-state maser.
- To investigate the underlying physics of DNP-enhanced NMR masers.
- To explain previously unexplained features of maser behavior.
Main Methods:
- Generation of a maser using proton spins hyperpolarized by DNP at cryogenic temperatures.
- Analysis of induction decays exhibiting multiple asymmetric maser pulses.
- Simulations of non-linear spin dynamics using Bloch-Maxwell-Provotrov (BMP) equations.
Main Results:
- Observed pulsed solid-state maser generated by DNP hyperpolarized proton spins.
- Confirmed unconventional maser behavior with negatively polarized spins.
- Simulations provided insights into radiation damping, DNP, and dipolar field effects.
Conclusions:
- The study presents new evidence for DNP NMR masers.
- Simulations using BMP equations help elucidate maser dynamics.
- The findings shed light on the complex behavior of these masers.
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