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Related papers: Surface segregation and the Al problem in GaAs qua…

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Density functional calculations with a large unit cell have been conducted to investigate adsorption, segregation and magnetization of Mn monomer on GaAs(110). The Mn adatom is rather mobile along the trench on GaAs(110), with an energy…

Statistical Mechanics · Physics 2009-11-11 J. X. Cao , X. G. Gong , R. Q. Wu

Topological defects are ubiquitous from solid state physics to cosmology, where they drive phase transitions by proliferating as domain walls, monopoles or vortices. As quantum excitations, they often display fractional charge and anyonic…

Mesoscale and Nanoscale Physics · Physics 2012-03-27 R. Koushik , Matthias Baenninger , Vijay Narayan , Subroto Mukerjee , Michael Pepper , Ian Farrer , David A. Ritchie , Arindam Ghosh

Achieving significant doping in GaAs/AlAs core/shell nanowires (NWs) is of considerable technological importance but remains a challenge due to the amphoteric behavior of the dopant atoms. Here we show that placing a narrow GaAs quantum…

Mesoscale and Nanoscale Physics · Physics 2014-04-24 J. Jadczak , P. Plochocka , A. Mitioglu , I. Breslavetz , M. Royo , A. Bertoni , G. Goldoni , T. Smolenski , P. Kossacki , Hadas Shtrikman , D. K. Maude

Quantum dot light-emitting diodes (QLEDs) are promising building blocks for prospective lighting and display applications. Despite the significant advancements achieved towards increasing the efficiency and brightness levels of QLEDs, the…

We present a detailed characterization of the growth dynamics of Ga(Al)As(111)A surfaces. We develop a theoretical growth model that well describes the observed behavior on the growth parameters and underlines the Ehrlich-Schwoebel barrier…

Materials Science · Physics 2017-07-12 Luca Esposito , Sergio Bietti , Alexey Fedorov , Richard Noetzel , Stefano Sanguinetti

Here, we report an alternative route to achieve two dimensional electron gas (2DEG) in a semiconductor structure. It has been shown that charge accumulation on the side facets can lead to the formation of 2DEG in a network of c-axis…

Mesoscale and Nanoscale Physics · Physics 2014-10-07 H. P. Bhasker , Varun Thakur , S. M. Shivaprasad , S. Dhar

We present a theoretical model of split-gate quantum wires that are fabricated from GaAs-AlGaAs heterostructures. The model is built on the physical properties of donors and of semiconductor surfaces, and considerations of equilibrium in…

Condensed Matter · Physics 2009-10-28 Yinlong Sun , George Kirczenow , Andrew. S. Sachrajda , Yan Feng

The two-dimensional topological insulator state in InAs/GaSb quantum wells manifests itself by topologically protected helical edge channel transport relying on an insulating bulk. This work investigates a way of suppressing bulk…

Low temperature scanning tunneling microscopy is used to image the doped topological insulator Bi$_{2-x}$Fe$_x$Se$_3$. Interstitial Fe defects allow the detection of quasiparticle interference (QPI), and the reconstruction of the empty…

We identify the physics behind the results of recent measurements [W. Kang et al., Nature 403, 59 (2000)] of electron transfer between the edges of two two-dimensional electron systems (2DES). We find that a consistent explanation of all of…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 Shinji Nonoyama , George Kirczenow

Two-dimensional (2D) ferroelectric (FE) materials are promising compounds for next-generation nonvolatile memories, due to their low energy consumption and high endurance. Among them, {\alpha}-In$_{2}$Se$_{3}$ has drawn particular attention…

We report experimental results on a quantum point contact (QPC) device formed in a wide AlAs quantum well where the two-dimensional electrons occupy two in-plane valleys with elliptical Fermi contours. To probe the closely-spaced,…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 O. Gunawan , B. Habib , E. P. De Poortere , M. Shayegan

We investigate high-mobility two-dimensional electron gases in AlGaAs heterostructures by employing Schottky-gate-dependent measurements of the samples' electron density and mobility. Surprisingly, we find that two different sample…

Mesoscale and Nanoscale Physics · Physics 2011-06-16 C. Rossler , T. Feil , P. Mensch , T. Ihn , K. Ensslin , D. Schuh , W. Wegscheider

The discovery of the fractional quantum Hall effect in GaAs-based semiconductor devices has lead to new advances in condensed matter physics, in particular the possibility for exotic, topological phases of matter that possess fractional,…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Z. Papic , D. A. Abanin , Y. Barlas , R. N. Bhatt

The polar interface between LaAlO$_{3}$ and SrTiO$_{3}$ has shown promise as a field effect transistor, with reduced (nanoscale) feature sizes and potentially added functionality over conventional semiconductor systems. However, the…

Mesoscale and Nanoscale Physics · Physics 2011-05-18 N. C. Bristowe , P. B. Littlewood , Emilio Artacho

In the present work, we were able to identify and characterize a new source of in-plane optical anisotropies (IOAs) occurring in asymmetric DQWs; namely a reduction of the symmetry from $D_{2d}$ to $C_{2v}$ as imposed by asymmetry along the…

The scope of this article is to review the state-of-the-art in the field of confined electron systems generated at the bare surfaces of transition metal oxides (TMOs). This scientific field is a prime example of a domain where…

Strongly Correlated Electrons · Physics 2017-11-22 Emmanouil Frantzeskakis , Tobias Chris Rödel , Franck Fortuna , Andrés Felipe Santander-Syro

Surface segregation of the low-molecular weight component in a polymeric mixture leads to degradation of industrial formulations. We report a simultaneous phase separation and surface migration phenomena in oligomer-polymer and oligomer-gel…

Soft Condensed Matter · Physics 2019-07-10 Biswaroop Mukherjee , Buddhapriya Chakrabarti

We report on transport signatures of hidden quantum Hall stripe (hQHS) phases in high ($N > 2$) half-filled Landau levels of Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum wells with varying Al mole fraction $x < 10^{-3}$. Residing…

Mesoscale and Nanoscale Physics · Physics 2020-12-17 X. Fu , Yi Huang , Q. Shi , B. I. Shklovskii , M. A. Zudov , G. C. Gardner , M. J. Manfra

This study is an optimization of GaAs and Al$_{0.55}$Ga$_{0.45}$As growth on GaAs (111)B substrates with a surface misorientation of 2{\deg} towards [$\bar{2}$11], aiming to enhance surface morphology. For quantum optical metasurfaces…

Materials Science · Physics 2025-03-04 T. Blaikie , M. C. Tam , S. Stich , M. Belkin , Z. R. Wasilewski