28 October

The road towards Floquet topological insulators

Friday 28 October 2016, 12:00pm

ICN2 Seminar Hall, ICN2 Building, UAB

Prof Luis E. F. Foa Torres - Departamento de Física, FCFM, Universidad de Chile, Santiago, Chile

Short abstract: Light-matter interaction is at the heart of intriguing phenomena and has led to many practical applications like, for instance, Raman spectroscopy. But beyond characterization, several studies have gone deeper into actually using light to modify the electrical properties of a material. This can be done, for example, by using light to switch off the conduction in graphene [1,2] (or other materials [3]), thereby allowing to tune the material's response with optical means, or even inducing tunable topological states in materials that would otherwise lack them [1,2,4,5,6,7,8] (i.e. a Floquet topological insulator [4]). The latter would expand the playground of topological insulators to a broader set of materials. Recently, laser-induced bandgaps have been experimentally verified at the surface of a topological insulator [3] adding much interest to this area. In this talk I will provide an overview of our recent works in this field with a focus on the generation of Floquet chiral edge states in graphene [6,9,10] (Fig. 1(a)), and other materials including topological insulators [8,11]. 

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