Accueil du site > Séminaires > LKB > Realizing Topological Phases with Neutral Atoms in Optical Lattices
Séminaire de Nathan Goldman (Univ. libre de Bruxelles)
Vendredi 11 février à 9h15 dans la salle de réunion du siège de l’IFRAF, au 4e etage du batiment Rataud, à l’ENS au 45 rue d’Ulm.
Résumé
Remarkably, such setups allow the tuning of fundamental features - such as the geometry and the dimensionality of the system, the interaction between the particles - with an exquisite precision. In this context, specific configurations of the external electromagnetic fields lead to non-trivial Berry’s phases [2], which mimic the presence of synthetic gauge fields in the cold atoms dynamics [3, 4]. Such gauge fields are extremely malleable and could lead to various fascinating effects stemming from condensed-matter and even high-energy physics [5].
In this talk, I will show how synthetic gauge fields can be dressed in optical lattice setups in order to realize topological states of matter. These quantum phases encode non-trivial topological order [6, 7] and lead to fascinating effects, such as the quantum Hall [8] and the quantum spin Hall effects [9]. Topological phases are extremely robust against perturbations caused by the experimental environments, and therefore, constitute potential candidates for quantum computing devices [9]. Generating topologically protected phases with cold atoms is an extremely attractive and realistic goal [10, 11], as it would offer an ideal playground to investigate their fundamental properties, such as their robustness against interactions and disorder.
I will discuss how topological phases can be engineered in an optical lattice and how one can trigger and detect phase transitions in these setups. Besides, I will discuss the interplay between topology, quantum transport and the pseudorelativistic regimes which can be reached in these systems.
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[9] M. Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010)
[10] T. D. Stanescu, V. Galitski and S. Das Sarma, Phys. Rev. A 82, 013608 (2010)
[11] N. Goldman, I. Satija, P. Nikolic, A. Bermudez, M. A. Martin-Delgado, M. Lewenstein and I. B. Spielman, Phys. Rev. Lett. 105, 255302 (2010).
N. Goldman
Center for Nonlinear Phenomena and Complex Systems - Universite Libre de Bruxelles , Belgium
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