Nonlinearity meets complexity: radio-frequency MASERs and dynamic nuclear polarization (DNP)
Dynamic nuclear polarization (DNP) techniques are capable to drive the nuclear spins out of equilibrium to a hyperpolarized state with polarizations up to 80-90%. Such very high magnetizations lead to nonlinear effects due to “radiation damping” inducing « maser » pulses, and dipolar field effects. Under certain experimental conditions, the NMR signal exhibits sustained maser pulses that persist for several minutes or hours, whilst typical solid state NMR signals disappear in less than a millisecond. In these unconventional conditions, phase coherence induced by radiation damping allows long range (weak) dipolar effects to be observed, which is unexpected in such conditions.
We will investigate the relations between the nonlinearities of the spin dynamics caused by radiation feedback and dipolar field effects, on the one hand, and DNP, on the other hand. Theoretical and numerical tools will be developed to investigate these complex systems. Experimental aspects will be explored to better understand the phenomena involved and the dynamics of the magnetization. An electronic feedback system to control radiation damping on a 6,7 T polarizer, but also in solution, on a conventional NMR spectrometer, will be implemented an developed to investigate the magnetization dynamics.
One position is opened, either for a postdoctoral researcher or a PhD candidate.
Interested postdoctoral candidates should have a PhD in physical sciences (Physics or Chemistry), with strong experience in fundamental aspects of NMR. Previous training in experimental physics and instrumentation, including hands-on experience with radiofrequency instrumentation are welcome.
Highly motivated PhD candidates should have a strong background in fundamental physical sciences, with at lest some knowledge in NMR. Also, training in experimental physics and instrumentation is recommended, as well as in scientific computing.
1- E. Weber, D. Kurzbach, D. Abergel Phys. Chem. Chem. Phys., 2019,21, 21278-21286 (DOI : 10.1039/C9CP03334C)
2- V. Thalakottoor, D. Abergel Phys. Chem. Chem. Phys., 2023,25, 10392-10404 (DOI : doi.org/10.1039/D2CP05696H)
-- Daniel Abergel Laboratoire des biomolécules - UMR7203 Département de chimie Ecole Normale Supérieure 24, rue Lhomond 75005 Paris Tel.: +33 1 44 32 32 65 email: firstname.lastname@example.org Kostya Ivanov Intercontinental NMR Seminars https://sites.google.com/view/nmr-seminar-series/home