Theory of finite pulse effects beyond perturbation limit: Challenges and Perspectives

Abstract

In this mini-review, we examine the exactness of the available theoretical methods for describing the effects of a radio frequency (RF) pulse on a spin I=1/2 system. Employing an isolated spin as a model system, the interplay between the internal (anisotropic) interactions and the external parameters (such as sample spinning frequency, amplitude of the pulse etc.) is discussed through comparison between simulations emerging from analytic and numerical methods. Accordingly, the suitability of the analytic methods are examined and classified into regimes based on the magnitudes of the internal and external parameters.