529-0443-01L  Advanced Magnetic Resonance

SemesterHerbstsemester 2022
DozierendeG. Jeschke, A. Barnes
Periodizität2-jährlich wiederkehrende Veranstaltung
LehrveranstaltungFindet dieses Semester nicht statt.

KurzbeschreibungThe course is for advanced students and covers selected topics from magnetic resonance spectroscopy. This semester, the lecture will introduce and discuss the dynamics of electron-nuclear spin systems and experiments based on hyperfine interactions in electron paramagnetic resonance (EPR) spectroscopy and dynamic nuclear polarization (DNP) for sensitivity enhancement in NMR.
LernzielThe course aims at enabling students to understand and design experiments that are based on hyperfine coupling between electron and nuclear spins. This includes analytical and numerical treatment of spin dynamics as well as instrumental aspects. Additionally, students will learn how to use hyperfine couplings to increase sensitivity in solid state NMR via dynamic nuclear polarization (DNP), with an emphasis on the instrumentation required to perform DNP with magic angle spinning (MAS) NMR.
InhaltThe course starts with a recapitulation of density operator and product operator formalism with special emphasis on electron-nuclear spin systems in the solid state. We then treat basic phenomena, such as passage effects, avoided level crossings, and hyperfine decoupling. Based on these foundations, we discuss polarization transfer from the electron to the nuclear spin and back, as well as spin diffusion as a mechanism for polarizing nuclear spins beyond the immediate vicinity of the electron spin. The second half of the course will cover dynamic nuclear polarization (DNP), with a focus on instrumentation required to perform pulsed DNP with magic angle spinning (MAS) at ultra-high magnetic fields. A review of salient interactions in the NMR solid state NMR Hamiltonian, DNP mechanisms, and electron decoupling with MAS will motivate discussions of technology development. Specific technologies to be covered include, but are not limited to, frequency agile gyrotron oscillators, corrugated waveguides, microwave lenses, strategies for creating pulsed and frequency chirped microwaves, spherical MAS rotors and supporting stators, high temperature superconductor (HTS) based compact magnets, and radio-frequency circuits for multinuclear spin control and detection.

Prerequisite: A basic knowledge of Magnetic Resonance, e.g. as covered in the Lecture Physical Chemistry IV, or the book "Spin Dynamics" by Malcolm Levitt.
SkriptA script which covers the topics will be distributed in the lecture and will be accessible through the course Moodle