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Related papers: Multiband $k \cdot p$ theory for hexagonal germani…

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In this work we present a comparison of multiband k.p-models, the effective bond-orbital approach, and an empirical tight-binding model to calculate the electronic structure for the example of a truncated pyramidal GaN/AlN self-assembled…

Materials Science · Physics 2009-11-13 Oliver Marquardt , Daniel Mourad , Stefan Schulz , Tilmann Hickel , Gerd Czycholl , Jörg Neugebauer

Several IV-VI semiconductor compounds made of heavy atoms, such as Pb$_{1-x}$Sn$_{x}$Te, may undergo band-inversion at the $L$ point of the Brillouin zone upon variation of their chemical composition. This inversion gives rise to…

Mesoscale and Nanoscale Physics · Physics 2018-05-28 A. Diaz-Fernandez , N. del Valle , F. Dominguez-Adame

The structural and electronic properties of zinc-blende (ZB) GaAs were calculated within the framework of plane wave density-functional theory (DFT) code JDFTx by using Becke 86 in 2D and PBE exchange correlation functionals from libXC. The…

Computational Physics · Physics 2019-11-26 Waqas Mahmood , Bing Dong

Germanium-silicon-germanium (Ge/Si$_{x}$Ge$_{1-x}$) heterostructures have emerged as a promising platform for hole-spin quantum technologies and high-mobility electronics, where strain and quantum confinement strongly reshape the Ge valence…

Quasi-one-dimensional hole gas is achievable in a semiconductor Ge nanowire. The lowest two subband dispersions of the hole gas are just two shifted parabolic curves with an anticrossing at $k_{z}=0$. This peculiar low-energy subband…

Mesoscale and Nanoscale Physics · Physics 2025-05-21 Rui Li

The electronic band structure of GaTe has been calculated by numerical atomic orbitals density-functional theory, in the local density approximation. In addition, the valence-band dispersion along various directions of the GaTe Brillouin…

We derive a nonsymmetrized 8-band effective-mass Hamiltonian for quantum-dot heterostructures (QDHs) in Burt's envelope-function representation. The 8x8 radial Hamiltonian and the boundary conditions for the Schroedinger equation are…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 E. P. Pokatilov , V. A. Fonoberov , V. M. Fomin , J. T. Devreese

Machine-learned multi-orbital tight-binding (MMTB) Hamiltonian models have been developed to describe the electronic characteristics of intermetallic compounds $\rm Mg_2Si, Mg_2Ge, Mg_2Sn$, and $\rm Mg_2Pb$ subject to strain. The MMTB…

Materials Science · Physics 2022-07-04 Mohammad Alidoust , Erling Rothmund , Jaakko Akola

We discuss the construction of low-energy tight-binding Hamiltonians for condensed matter systems with a strong coupling to the quantum electromagnetic field. Such Hamiltonians can be obtained by projecting the continuum theory on a given…

Strongly Correlated Electrons · Physics 2020-05-27 Jiajun Li , Denis Golez , Giacomo Mazza , Andrew Millis , Antoine Georges , Martin Eckstein

A new method for calculation of band structure has been proposed based on the Green's function theory and local sampling. Potential energy in the Hamiltonian of Schrodinger's equation is approximated with a series of sampled Dirac delta…

Mesoscale and Nanoscale Physics · Physics 2010-02-24 Milad Khoshnegar , Sina Khorasani , Amirhossein Hosseinnia

We calculate the electronic structures of Germanium nanowires by taking the effective-mass theory. The electron and hole states at the G-valley are studied via the eight-band k.p theory. For the [111] L-valley, we expand the envelope wave…

Optics · Physics 2019-10-25 Wen Xiong , Jian-Wei Wang , Wei-Jun Fan , Zhi-Gang Song , Chuan-Seng Tan

Strain provides a powerful knob to tailor the electronic properties of semiconductors. Simple yet accurate approximations that capture strain effects in demanding simulations of mesoscopic nanostructures are therefore highly desirable.…

Materials Science · Physics 2025-09-17 Samuel D. Escribano , Alfredo Levy Yeyati , Elsa Prada

Before assessing the suitability of a semiconductor for specific applications, the first question to ask is whether it possesses a direct or indirect band gap. This distinction is fundamental, as the operation of devices such as…

We report on a theoretical study of the electronic structures of freestanding nanowires made from narrow band gap semiconductors GaSb, InSb and InAs. The nanowires are described by the eight-band k.p Hamiltonians and the band structures are…

Mesoscale and Nanoscale Physics · Physics 2016-12-30 Ning Luo , Gaohua Liao , H. Q. Xu

Complementary angle-resolved photoemission and bulk-sensitive k-resolved resonant inelastic x-ray scattering of divalent hexaborides reveal a >1 eV X-point gap between the valence and conduction bands, in contradiction to the band overlap…

Strongly Correlated Electrons · Physics 2009-11-07 J. D. Denlinger , J. A. Clack , J. W. Allen , G. -H. Gweon , D. M. Poirier , C. G. Olson , J. L. Sarrao , A. D. Bianchi , Z. Fisk

High-quality defect-free lonsdaleite Si and Ge can now be grown on hexagonal nanowire substrates. These hexagonal phases of group-IV semiconductors have been predicted to exhibit improved electronic and optical properties for optoelectronic…

We study the electronic band structure in the K/K' valleys of the Brillouin zone of monolayer WSe2 and MoSe2 by optical reflection and photoluminescence spectroscopy on dual-gated field-effect devices. Our experiment reveals the distinct…

Mesoscale and Nanoscale Physics · Physics 2017-02-21 Zefang Wang , Liang Zhao , Kin Fai Mak , Jie Shan

The direct measurement of Berry phases is still a great challenge in condensed matter systems. The bottleneck has been the ability to adiabatically drive an electron coherently across a large portion of the Brillouin zone in a solid where…

We theoretically investigate the properties of holes in a Si$_{x}$Ge$_{1-x}$/Ge/ Si$_{x}$Ge$_{1-x}$ quantum well in a perpendicular magnetic field that make them advantageous as qubits, including a large ($>$100~meV) intrinsic splitting…

Based on experimental data on the newly synthesized iron-based superconductors and the relevant band structure calculations, we propose a minimal two-band BCS-type Hamiltonian with the interband Hubbard interaction included. We illustrate…

Superconductivity · Physics 2009-11-13 Q. Han , Y. Chen , Z. D. Wang