Theoretical Background

  • Javier Galego PascualEmail author
Part of the Springer Theses book series (Springer Theses)


This chapter presents the essential theoretical background necessary to explain some of the most important concepts discussed throughout this thesis. The aim is to provide the reader with the basic tools to understand the many fundamental equations and approximations used in the contexts of cavity quantum electrodynamics (CQED) and quantum chemistry. We start by addressing the question of what is the quantum Hamiltonian for the light–matter interaction and illustrating what approximations play an important role in its definition. We then focus on the matter part of the light–matter Hamiltonian in order to provide the best possible description of a complex molecule. In this section we address the Born–Oppenheimer approximation, widely used in molecular and solid-state physics and in quantum chemistry. Additionally, we present the description of different characteristic phenomena of organic molecules such as chemical structure and reactions, and their response to the electromagnetic field. Then, we focus on this last part, discussing the important features of CQED and the different theoretical descriptions that study them. Finally we present the fundamentals of the two different regimes of light–matter interaction: weak and strong coupling.


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© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Física teórica de la materia condensadaUniversidad Autónoma de MadridMadridSpain

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