Soutenance de thèse de Kirill Plekhanov et Mini-workshop on Topology in condensed matter

Soutenance de thèse le Vendredi 7 septembre 2018, 9h30

LPTMS, Bâtiment 100, 15 Rue Georges Clemenceau, 91405 Orsay (http://lptms.u-psud.fr/en/locations/lptms-batiment-100-salle-201-orsay/)

Kirill Plekhanov
(Equipe Matière condensée)

"Topological Floquet States, artificial gauge fields in strongly correlated quantum fluid"

Abstract : In this thesis we study the topological aspects of condensed matter physics, that received a revolutionary development in the last decades. Topological states of matter are protected against perturbations and disorder, making them very promising in the context of quantum information. The interplay between topology and interactions in such systems is however far from being well understood, while the experimental realization is challenging. Thus, in this work we investigate such strongly correlated states of matter and explore new protocols to probe experimentally their properties. In order to do this, we use various both analytical and numerical techniques.

First, we analyze the properties of an interacting bosonic version of the celebrated Haldane model – the model for the quantum anomalous Hall effect. We propose its quantum circuit implementation based on the application of periodic time-dependent perturbations – Floquet engineering. Continuing these ideas, we study the interacting bosonic version of the Kane-Mele model – the first model of a topological insulator. This model has a very rich phase diagram with an emergence of an effective frustrated magnetic model and a variety of symmetry broken spin states in the strongly interacting regime. Ultra-cold atoms or quantum circuits implementation of both Haldane and Kane-Mele bosonic models would allow for experimental probes of the exotic states we observed.

Second, in order to deepen the perspectives of quantum circuit simulations of topological phases we analyze the strong coupling limit of the Su-Schrieffer-Heeger model and we test new experimental probes of its topology associated with the Zak phase. We also work on the out-of-equilibrium protocols to study bulk spectral properties of quantum systems and quantum phase transitions using a purification scheme which could be implemented both numerically and experimentally.

La soutenance sera suivi d'un mini workshop :

Mini-workshop on Topology in condensed matter -- 13:30 - 17:00

13:30-14:00: Walter Hofstetter
14:00-14:30: Titus Neupert
14:30-15:00 : Nathan Goldman
15:00-15:30: pause
15:30-16:00 : Guido Pupillo
16:00-16:30: Nicolas Regnault
16:30-17:00: Mark Oliver Goerbig