Concept

K·p perturbation theory

Related publications (17)

Correlating chemical and electronic states from quantitative photoemission electron microscopy of transition-metal dichalcogenide heterostructures

Andras Kis, Dumitru Dumcenco, Olivier Renault, Dmitrii Unuchek, Hokwon Kim, Nicolas Chevalier

Vertical heterostructures of MoS2 and WSe2 layers are studied by spectroscopic photoemission electron microscopy as an effective technique for correlating chemical and electronic states at the micrometer scale. Element-specific, surface-sensitive images re ...

2021

Probing intraband excitations in ZrTe5: A high-pressure infrared and transport study

Mathieu François Padlewski, Helmuth Berger, Philip Johannes Walter Moll, Ana Akrap

Zirconium pentatetelluride, ZrTe5, shows remarkable sensitivity to hydrostatic pressure. In this work we address the high-pressure transport and optical properties of this compound, on samples grown by flux and chemical vapor transport. The high-pressure r ...

2020

Dynamics of excited interlayer states in hexagonal boron nitride monolayers

Josef Andreas Schuler

Hexagonal boron nitride () is the isoelectronic but insulating counterpart of graphene. Like graphene it can easily be grown as high-quality nanotubes or as single layers on metal surfaces. Both materials can be exfoliated or transferred after single-layer ...

2020

Ultrathin Junctionless Nanowire FET Model, Including 2-D Quantum Confinements

Farzan Jazaeri

In this paper, we develop an explicit model to predict the dc electrical behavior in ultrathin surrounding gate junctionless (JL) nanowire field-effect transistors (FETs). The proposed model considers 2-D electrical and geometrical confinements of carrier ...

2019

Scaling of the superconducting gap with orbital character in FeSe

Timur Kim

We use high-resolution angle-resolved photoemission spectroscopy to map the three-dimensional momentum dependence of the superconducting gap in FeSe. We find that on both the hole and electron Fermi surfaces, the magnitude of the gap follows the distributi ...

2018

Electrochemical potential window of battery electrolytes: the HOMO-LUMO misconception

Hubert Girault, Pekka Eero Peljo

A widespread misconception in the lithium ion battery literature is the equality of the energy difference of HOMO and LUMO of the solvent with the electrochemical stability window. HOMO and LUMO are concepts derived from approximated electronic structure t ...

2018

Valence Level Character in a Mixed Perovskite Material and Determination of the Valence Band Maximum from Photoelectron Spectroscopy: Variation with Photon Energy

Ulf Anders Hagfeldt, Juan-Pablo Correa-Baena, Tor Jesper Jacobsson

A better understanding of the electronic structure of perovskite materials used in photovoltaic devices is essential for their development and optimization. In this investigation, synchrotron-based photoelectron spectroscopy (PES) was used to experimentall ...

American Chemical Society2017

A Theoretical Investigation of Topological Insulator Nanostructures

Naunidh Singh Virk

The topology of the electron wavefunctions in certain band insulators can give rise to novel topological phases. Materials harbouring such topological phases are termed topological insulators (TI). A gapped bulk electronic spectrum, described by a topologi ...

EPFL2016

Fermi states and anisotropy of Brillouin zone scattering in the decagonal Al-Ni-Co quasicrystal

Jan Hugo Dil, Thorsten Schmitt

Quasicrystals (QCs) are intermetallic alloys that have excellent long-range order but lack translational symmetry in at least one dimension. The valence band electronic structure near the Fermi energy E-F in such materials is of special interest since it h ...

Nature Publishing Group2015

An updated version of wannier90: A tool for obtaining maximally-localised Wannier functions

Nicola Marzari, Giovanni Pizzi

wannier90 is a program for calculating maximally-localised Wannier functions (MLWFs) from a set of Bloch energy bands that may or may not be attached to or mixed with other bands. The formalism works by minimising the total spread of the MLWFs in real spac ...

Elsevier Science Bv2014

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