Application of Floquet-Magnus Expansion During the Phase Modulated Lee-Goldburg Radiation in Solid State NMR

Abstract

This work uses the Floquet-Magnus expansion approach to investigate the spin system evolution during the phase modulate Lee-Goldburg radiation experiment. Until now, the Frequency switched LeeGoldburg and its variant called the Phase module Lee-Goldburg have been treated by only the average Hamiltonian theory and the bimodal Floquet approach. In this article, we use the expansion schemes of the Floquet-Magnus expansion to calculate the effective Hamiltonian and propagator during the spin dynamics. We present a remarkable iterative approach for the Floquet-Magnus expansion. Our work unifies and generalizes existing results of the Floquet-Magnus expansion and delivers illustrations of novel springs that boost previous applications that are based on the classical information. The method presented could plays a major role in the interpretation of a number of fine NMR experiments in solids, which provide significant new insight in spin physics. The generality of the work points to potential applications in problems related in solid-state NMR and theoretical developments of spectroscopy as well as interdisciplinary research areas whenever they include spin dynamics concepts. The considered method of Floquet-Magnus expansion has recently found new major areas of applications such as in topological materials..