2D materials under the microscope(s): connecting material properties and electronic structure to many-body excitonic phenomena in monolayer WS2 (Conference Presentation)

2018 ◽  
Author(s):  
Christoph Kastl ◽  
Roland Koch ◽  
Chris Chen ◽  
Johanna Eichhorn ◽  
Bruno Schuler ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Material Properties ◽  
2D Materials ◽  
Many Body

First principles study of the structural, electronic and optical properties of crystalline o-phenanthroline

2016 ◽  
Vol 30 (14) ◽  
pp. 1650077 ◽  
Author(s):  
Hajar Nejatipour ◽  
Mehrdad Dadsetani
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
First Principles ◽  
Binding Energies ◽  
Many Body ◽  
Generalized Gradient ◽  
Generalized Gradient Approximation ◽  
Independent Particle ◽  
Excitonic Effects ◽  
Comprehensive Study

In a comprehensive study, structural properties, electronic structure and optical response of crystalline o-phenanthroline were investigated. Our results show that in generalized gradient approximation (GGA) approximation, o-phenanthroline is a direct bandgap semiconductor of 2.60 eV. In the framework of many-body approach, by solving the Bethe–Salpeter equation (BSE), dielectric properties of crystalline o-phenanthroline were studied and compared with phenanthrene. Highly anisotropic components of the imaginary part of the macroscopic dielectric function in o-phenanthroline show four main excitonic features in the bandgap region. In comparison to phenanthrene, these excitons occur at lower energies. Due to smaller bond lengths originated from the polarity nature of bonds in presence of nitrogen atoms, denser packing, and therefore, a weaker screening effect, exciton binding energies in o-phenanthroline were found to be larger than those in phenanthrene. Our results showed that in comparison to the independent-particle picture, excitonic effects highly redistribute the oscillator strength.

scholarly journals Many-body electronic structure and Kondo properties of cobalt-porphyrin molecules

2009 ◽  
Vol 80 (15) ◽  
Author(s):  
Luis G. G. V. Dias da Silva ◽  
Murilo L. Tiago ◽  
Sergio E. Ulloa ◽  
Fernando A. Reboredo ◽  
Elbio Dagotto
Keyword(s):  
Electronic Structure ◽  
Many Body ◽  
Cobalt Porphyrin

scholarly journals Automatic code generation for many-body electronic structure methods: the tensor contraction engine‡‡

2006 ◽  
Vol 104 (2) ◽  
pp. 211-228 ◽  
Author(s):  
Alexander A. Auer ◽  
Gerald Baumgartner ◽  
David E. Bernholdt ◽  
Alina Bibireata ◽  
Venkatesh Choppella ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Code Generation ◽  
Automatic Code Generation ◽  
Many Body ◽  
Electronic Structure Methods ◽  
Tensor Contraction ◽  
Automatic Code

Many-Body Effects in the Electronic Structure of Topological Insulators

2015 ◽  
pp. 161-189
Author(s):  
Irene Aguilera ◽  
Ilya A. Nechaev ◽  
Christoph Friedrich ◽  
Stefan Blügel ◽  
Evgueni V. Chulkov
Keyword(s):  
Electronic Structure ◽  
Topological Insulators ◽  
Many Body ◽  
Many Body Effects

scholarly journals Strain-induced effects on the electronic properties of 2D materials

2020 ◽  
Vol 10 ◽  
pp. 184798042090256 ◽  
Author(s):  
Sara Postorino ◽  
Davide Grassano ◽  
Marco D’Alessandro ◽  
Andrea Pianetti ◽  
Olivia Pulci ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Density Functional ◽  
2D Materials ◽  
Transition Metal Dichalcogenides ◽  
Many Body ◽  
Functional Theory ◽  
Metal Dichalcogenides ◽  
Extreme Sensitivity ◽  
Nonuniform Strain

Thanks to the ultrahigh flexibility of 2D materials and to their extreme sensitivity to applied strain, there is currently a strong interest in studying and understanding how their electronic properties can be modulated by applying a uniform or nonuniform strain. In this work, using density functional theory (DFT) calculations, we discuss how uniform biaxial strain affects the electronic properties, such as ionization potential, electron affinity, electronic gap, and work function, of different classes of 2D materials from X-enes to nitrides and transition metal dichalcogenides. The analysis of the states in terms of atomic orbitals allows to explain the observed trends and to highlight similarities and differences among the various materials. Moreover, the role of many-body effects on the predicted electronic properties is discussed in one of the studied systems. We show that the trends with strain, calculated at the GW level of approximation, are qualitatively similar to the DFT ones solely when there is no change in the character of the valence and conduction states near the gap.

Sign in / Sign up

Export Citation Format

Share Document