This dissertation focuses on one question: how should one drive an experimentally prepared state of a generic quantum system into a different target-state, simultaneously minimizing energy dissipation and maximizing the fidelity between the target and evolved-states? We develop optimal adiabatic driving protocols for general quantum systems, and show that these are geodesic paths. Geometric ideas have always played a fundamental role in the understanding and unification of physical phenomena, and the recent discovery of topological insulators has drawn great interest to topology from the field of condensed matter physics. Here, we discuss the quantum geometric tensor, a mathematical object that encodes geometrical and topological properties of a quantum system. It is related to the fidelity susceptibility (an important quantity regarding quantum phase transitions) and to the Berry curvature, which enables topological characterization through Berry phases. A refined understanding of the interplay between geometry and topology in quantum mechanics is of direct relevance to several emergent technologies, such as quantum computers, quantum cryptography, and quantum sensors. As a demonstration of how powerful geometric and topological ideas can become when combined, we present the results of an experiment that we recently proposed. This experimental work was done at the Google Quantum Lab, where researchers were able to visualize the topological nature of a two-qubit system in sharp detail, a startling contrast with earlier methods. To achieve this feat, the optimal protocols described in this dissertation were used, allowing for a great improvement on the experimental apparatus, without the need for technical engineering advances. Expanding the existing literature on the quantum geometric tensor using notions from differential geometry and topology, we build on the subject nowadays known as quantum geometry. We discuss how slowly changing a parameter of a quantum system produces a measurable output of its response, merely due to its geometric nature. Next, we topologically characterize different classes of Hamiltonians using the Berry monopole charges, and establish their topological protection. Finally, we explore how such knowledge allows one to access topologically forbidden regions by adiabatically breaking and reestablishing symmetries.

Dans cette thèse, on définit un invariant fonctoriel d'enchevêtrements dans le tore épaissi qui généralise l'intégrale de Kontsevich. Cet invariant est tout d'abord construit analytiquement à partir d'une version universelle de la connexion de Knizhnik-Zamolodchikov-Bernard elliptique. On donne ensuite une version combinatoire de sa construction, basée sur la notion d' « associateur elliptique » introduite par Enriquez. L'outil principal de cette dernière construction est un théorème qui caractérise la catégorie des enchevêtrements en genre quelconque par une propriété universelle exprimée dans le langage des catégories tensorielles. / We construct a functorial invariant of tangles embedded in the thickened torus. This invariant generalizes the Kontsevich integral, and can be analytically derivated from a universal version of the elliptic Knizhnik-Zamolodchikov-Bernard equation. The main part of the thesis is devoted to the combinatorial version of its construction, using the notion of « elliptic associator » introduced by Enriquez. A key ingredient is a universal property satisfied by the category of framed tangles in the torus. This universal property is established in the language of monoidal categories, and extends Reshetikhin-Turaev-Shum's coherence theorem to the case of framed tangles in any closed genus g surface.