From The Holstein-Primakoff Transformation to Semiclassical Quantum Markovian Master Equations – with Applications in Magnetic Resonance

[from the Preface]: The present dissertation concerns some theoretical and computational aspects of multispin dynamics, mainly, in relation to magnetic resonance. ... The present dissertation is divided into five parts. Part I provides a quick overview of some fundamental concepts in quantum mechanics. The HP transformation is extensively discussed in Part II. Concepts from the theory of open quantum systems like completely positive maps, universal dynamical maps, quantum dynamical semigroups and quantum Markovian master equations are discussed in Part III. This is where we also refine, to some degree, many of these fundamental concepts. Part IV brings together concepts developed in Parts II and III. There, we introduce our proposal on how to still apply many of the ideas and concepts from open quantum system theory (the Gorini-Kossakowski-Sudarshan- Lindblad approach) even when the environment is treated at the classical level. In particular, we discuss semiclassical quantum Markovian master equations and apply it to describe continuous wave magnetic resonance of multispin spin systems. The ACP scheme is also introduced in Part IV. Conclusion and perspectives on the work are given in Part V