Chalcogenide Nanosheets: Optical Signatures of Many-Body Effects and Electronic Band Structure

Part of the Nanostructure Science and Technology book series (NST)


Layered chalcogenide materials exhibit a wide range of physical properties associated with their quasi-2D nature and have been studied extensively since the second half of the twentieth century. Following the discovery of graphene, the ability to isolate individual monolayer of these material has recently opened up numerous avenues for probing various physical effects in the ultimate 2D confinement limit. Monolayers of group 6 transition metal dichalcogenides are an attractive platform for studying many-body effects, non-linear optics, and valley physics. Along with other emerging 2D chalcogenides, they offer unique opportunities for realizing novel devices and their technological implementations. Here we review the fundamental properties of various semiconducting chalcogenide nanosheets and their heterostructures with emphasis on the electronic structure and optical properties of Mo- and W-based dichalcogenides (MoS2, MoSe2, MoTe2, WS2, WSe2). We discuss the current understanding on the the layer-dependent energy dispersion and and its optical signatures in these material systems. We further discuss the strong excitonic effects and review recent experimental efforts in estimating exciton binding energy using various optical and opto-electrical approaches.


Density Functional Theory Calculation Exciton Binding Energy Conduction Band Minimum Monolayer MoS2 Scanning Tunneling Spectroscopy 







Two-photon photoluminescence excitation


Annular dark field


Atomic layer deposition


Angle-resolved photoemission spectroscopy


Bilayer graphene


Conduction band minimum


Charge density wave




Chemical vapor deposition


Chemical vapor transport


Density functional theory


Density of state


Differential reflectance


Highly oriented pyrolytic graphite


Joint density of states


Molecular beam epitaxy


Metal atoms (M) and chalcogen atoms (X)








Photoluminescence excitation spectroscopy


Second harmonic generation spectroscopy


Scanning transmission electron microscopy


Scanning tunneling microscopy


Scanning tunneling spectroscopy


Transient absorption


Transition metal dichalcogenide


Valence band maximum


X-ray photoelectron spectroscopy


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Copyright information

© Springer Japan KK 2017

Authors and Affiliations

  1. 1.Department of PhysicsNational University of SingaporeSingaporeSingapore
  2. 2.Department of ChemistryNational University of SingaporeSingaporeSingapore
  3. 3.Centre for Advanced 2D MaterialsNational University of SingaporeSingaporeSingapore

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