Speaker: Steven G. Louie
Physics Department, University of California at Berkeley, and Lawrence Berkeley National Lab
Title：Some Novel Phenomena in Atomically Thin Quasi 2D Materials
Time: 15:00-16:00, Oct. 12
Avenue： Physics Building 221B Meeting Room
Abstract：Experimental and theoretical studies of atomically thin quasi two-dimensional (2D) materials and their nanostructures have revealed that these systems can exhibit highly unusual behaviors. Owing to their reduced dimensionality, quasi-2D materials present opportunities for manifestation of concepts/phenomena that may not be so prominent or have not been seen in bulk materials. Symmetry, many-body interaction, and substrate screening effects often play a critical role in shaping qualitatively and quantitatively their electronic, transport and optical properties, and thus their potential for applications. In this talk, we present theoretical studies on quasi-2D systems such as monolayer and few-layer transition metal dichalcogenides (e.g., MoS2, MoSe2, WS2, and WSe2) and metal monochalcogenides (such as GaSe) as well as graphene. Several quantum phenomena are discussed, including massless excitons and tunable magnetism in these materials. We investigate their physical origins and compare theoretical predictions with experimental data.
