Physics

Biography

Biography: Eugene Stephane Mananga

Abstract

We present two alternative expansion scheme called Floquet-Magnus expansion used to solve a time-dependent linear differential equation which is a central problem in quantum physics in general and solid-state nuclear magnetic resonance (NMR) in particular. The commonly used methods to treat theoretical problems in solid-state NMR are the average Hamiltonian theory and the Floquet theory, which have been successful for designing sophisticated pulse sequences and understanding of different experiments. The topic of the talk opens a way to an infinite number of suggestions. However, it is very important to remember that the Fer and Floquet-Magnus expansions method have recently found new major areas of applications such as topological materials. Researchers, dealing with those new applications, are not usually acquainted with the achievements of the magnetic resonance theory, where those methods were developed more than 30 years ago. They repeat the same mistakes that were made when the methods of spin dynamics and thermodynamics were developed in the past. This talk is very useful not only for the NMR and physics communities but for the new communities in several younger fields. It will be very useful for scientists working in different directions. In this talk, I will compare both approaches (Fer and Floquet-Magnus expansions) and present their use for the calculation of effective Hamiltonians and propagators, the performance of explicit calculation for the Bloch-Siegert shift, heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance recoupling. This presentation contributes theoretically and numerically in the general field of spin dynamics and physics.