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Related papers: Atomic structure of Ge quantum dots on the Si(001)…

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Clean two-dimensional electron systems in GaAs/AlGaAs heterostructures exhibit anisotropic collective phases, the quantum Hall nematics, at high Landau level occupancy and low temperatures. An as yet unknown native symmetry-breaking…

Mesoscale and Nanoscale Physics · Physics 2015-09-16 J. Pollanen , K. B. Cooper , S. Brandsen , J. P. Eisenstein , L. N. Pfeiffer , K. W. West

The one-dimensional reconstruction of Au/Ge(001) was investigated by means of autocorrelation functions from surface x-ray diffraction (SXRD) and scanning tunneling microscopy (STM). Interatomic distances found in the SXRD-Patterson map are…

Strongly Correlated Electrons · Physics 2013-05-30 S. Meyer , T. Umbach , C. Blumenstein , J. Schäfer , R. Claessen , S. Sauer , S. J. Leake , P. R. Willmott , M. Fiedler , F. Bechstedt

We demonstrate nearly-spherical, strain-free, self-assembled Ge quantum dots (QDs) fully encapsulated by AlAs, grown on (100) GaAs by molecular beam epitaxy (MBE). The QDs were formed without a wetting layer using a high temperature,…

Using the plane wave pseudopotential method we performed density functional theory calculations on the stability of steps and self-diffusion processes on Ag(100). Our calculated step formation energies show that the {111}-faceted step is…

Materials Science · Physics 2009-10-28 Byung Deok Yu , Matthias Scheffler

The ordering of N equally charged particles (-e) moving in two dimensions and confined by a Coulomb potential, resulting from a displaced positive charge Ze is discussed. This is a classical model system for atoms. We obtain the…

Strongly Correlated Electrons · Physics 2007-05-23 W. P. Ferreira , A. Matulis , G. A. Farias , F. M. Peeters

Density functional and quantum Monte Carlo calculations challenge the existence of a unique ground state structure for certain Si clusters. For Si clusters with more than a dozen atoms the lowest ten isomers are close in energy and for some…

Materials Science · Physics 2009-11-11 W. Hellmann , R. Hennig , S. Goedecker , C. Umrigar , B. Delley , T. Lenosky

Nuclear structures of the atomic nuclei can be theoretically investigated by using nuclear shell model. Generally, a doubly closed-shell nucleus has been considered as inert core and the nucleons outside the core are taken into account in…

Nuclear Theory · Physics 2020-04-14 Serkan Akkoyun , Tuncay Bayram

According to microscopic calculations with antisymmetrized molecular dynamics, we studied cluster features in stable and unstable nuclei. A variety of structure was found in stable and unstable nuclei in the $p$-shell and $sd$-shell…

Nuclear Theory · Physics 2015-06-26 Y. Kanada-En'yo , M. Kimura , H. Horiuchi

We have performed total-energy density-functional calculations using first-principles pseudopotentials to determine the atomic and electronic structure of neutral surface and subsurface vacancies at the GaP(110) surface. The cation as well…

Materials Science · Physics 2009-10-30 G. Schwarz , A. Kley , J. Neugebauer , M. Scheffler

Background: In the mass regions with an abnormal shell structure, the so-called ``island of inversion," the spin-parity of odd-mass nuclei provides quantitative insights into the shell evolution. However, the experimental determination of…

Nuclear Theory · Physics 2026-03-19 R. Barman , W. Horiuchi , M. Kimura , R. Chatterjee

Pt deposited on a Ge(001) surface spontaneously forms nanowire arrays. These nanowires are thermodynamically stable and can be hundreds of atoms long. The nanowires only occur on a reconstructed Pt-Ge-surface where they fill the troughs…

Materials Science · Physics 2013-11-15 Danny E. P. Vanpoucke , Geert Brocks

Composition, atomic structure, and electronic properties of TM$_x$Mg$_y$O$_z$ clusters (TM = Cr, Ni, Fe, Co, $x+y \leq 3$) at realistic temperature $T$ and partial oxygen pressure $p_{\textrm{O}_2}$ conditions are explored using the {\em ab…

The oxidized Ag(111) surface has been studied by a combination of experimental and theoretical methods, scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), and density functional theory (DFT). A large variety of…

We propose a new variety of silicon quantum dots containing fullerene-derived hollows of nearly arbitrary symmetry. Conglomerate structures are designed by connecting the quantum dots through two kinds of junctions. The quantum confinement…

The initial steps of MBE growth of GaAs on beta 2-reconstructed GaAs(001) are investigated by performing total energy and electronic structure calculations using density functional theory and a repeated slab model of the surface. We study…

Condensed Matter · Physics 2009-10-31 P. Kratzer , C. G. Morgan , M. Scheffler

Liquids and solids are two fundamental states of matter. However, due to the lack of direct experimental determination, our understanding of the 3D atomic structure of liquids and amorphous solids remained speculative. Here we advance…

We use first principles simulations to investigate the electronic properties of a set of carbon nanocages with a bipartite structure. These nanocages are exclusively formed by hexagonal and tetragonal rings and we show they feature frontier…

The interaction between spins in coupled quantum dots is revealed in distinct fine structure patterns in the measured optical spectra of InAs/GaAs double quantum dot molecules containing zero, one, or two excess holes. The fine structure is…

Other Condensed Matter · Physics 2011-11-09 M. Scheibner , M. F. Doty , I. V. Ponomarev , A. S. Bracker , E. A. Stinaff , V. L. Korenev , T. L. Reinecke , D. Gammon

We examine the structure and the evolution of Ge islands epitaxially grown on vicinal Si(111) surfaces by scanning tunneling microscopy. Contrary to what is observed on the singular surface, three-dimensional Ge nanoislands form directly…

Mesoscale and Nanoscale Physics · Physics 2011-10-25 L. Persichetti , R. Menditto , A. Sgarlata , M. Fanfoni , A. Balzarotti

Atomic nuclei in general can have deformed shapes and nearly all these shapes are symmetric with respect to reflection. Only a few Actinide nuclei have stable reflection asymmetric pear shapes in their ground state and exhibit…