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Related papers: CdS/HgS/CdS Quantum Dot Quantum Wells: A Tight-bin…

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A whole series of complementary studies have been performed on the same, single nanowire containing a quantum dot: cathodoluminescence spectroscopy and imaging, micro-photoluminescence spectroscopy under magnetic field and as a function of…

Optical properties of multilayer semi-conductor nano-emitters are crucially dependent on the relative energy levelsof their different components. For core/shell quantum dots, the relative energy difference between conduction bandedge of…

Semiconductor nanoplatelets possess exceptional optical properties that make them promising candidates for next-generation optoelectronic applications. However, unlike quantum dots where absorption spectroscopy alone can determine both size…

An optical method is suggested to determine the concentration of two-dimensional electrons in modulation-doped quantum wells at low and moderate electron densities between 10^{9} and 2x10^{11} cm^{-2}. The method is based on an analysis of…

The search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These topological insulators have an insulating gap in…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Markus Koenig , Hartmut Buhmann , Laurens W. Molenkamp , Taylor L. Hughes , Chao-Xing Liu , Xiao-Liang Qi , Shou-Cheng Zhang

Quantum dot (QD) assemblies are nanostructured networks made from aggregates of QDs and feature improved charge and energy transfer efficiencies compared to discrete QDs. Using first-principles many-body perturbation theory, we…

Materials Science · Physics 2022-10-25 Sandip Aryal , Joseph Frimpong , Zhen-Fei Liu

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…

Silicon nanocrystals with diameters between 1 and 3 nm and surfaces passivated by chlorine or a mixture of chlorine and hydrogen were modeled using density functional theory, and their properties compared with those of fully hydrogenated…

Mesoscale and Nanoscale Physics · Physics 2013-11-06 A. Carvalho , S. Öberg , M. J. Rayson , P. R. Briddon

Large-area high density patterns of quantum dots with a diameter of 200 nm have been prepared from a series of four Zn_{0.93}Mn_{0.07}Te/ZnTe multiple quantum well structures of different well width (4 nm, 6 nm, 8 nm and 10 nm) by electron…

Materials Science · Physics 2009-10-30 P. J. Klar , D. Wolverson , D. E. Ashenford , B. Lunn , Torsten Henning

We report an experimental investigation of fractional quantum Hall effect (FQHE) at the even-denominator Landau level filling factor $\nu$ = 1/2 in very high quality wide GaAs quantum wells, and at very high magnetic fields up to 45 T. The…

Mesoscale and Nanoscale Physics · Physics 2013-12-24 J. Shabani , Y. Liu , M. Shayegan , L. N. Pfeiffer , K. W. West , K. W. Baldwin

Crystallographic point defects (PDs) can dramatically decrease the efficiency of optoelectronic semiconductor devices, many of which are based on quantum well (QW) heterostructures. However, spatially resolving individual non-radiative PDs…

Using time-resolved photoluminescence spectroscopy, we studied the electronic levels of semiconductor nanocrystals (NCs) with small spin-orbit coupling such as CdS. Low temperature radiative rates indicate that the lowest energy transition…

Mesoscale and Nanoscale Physics · Physics 2009-10-15 Boqian Yang , James E. Schneeloch , Zhenwen Pan , Madalina Furis , Marc Achermann

To gain a deeper understanding of the luminescence of multiquantum wells and the factors affecting it on a microscopic level, cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to reveal…

Applied Physics · Physics 2023-09-15 Zhetong Liu , Bingyao Liu , Dongdong Liang , Xiaomei Li , Xiaomin Li , Li Chen , Rui Zhu , Jun Xu , Tongbo Wei , Xuedong Bai , Peng Gao

Time-resolved Faraday rotation studies of CdS/CdSe/CdS quantum-dot quantum wells have recently shown that the Faraday rotation angle exhibits several well-defined resonances as a function of probe energy close to the absorption edge. Here,…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Florian Meier , David D. Awschalom

The structure of the electron quantum size levels in spherical nanocrystals is studied in the framework of an eight--band effective mass model at zero and weak magnetic fields. The effect of the nanocrystal surface is modeled through the…

Materials Science · Physics 2009-11-07 A. V. Rodina , Al. L. Efros , A. Yu. Alekseev

We present evidence of cavity quantum electrodynamics from a sparse density of strongly quantum-confined Pb-chalcogenide nanocrystals (between 1 and 10) approaching single-dot levels on moderately high-Q mesoscopic silicon optical cavities.…

Quantum Physics · Physics 2015-05-13 Ranojoy Bose , Jie Gao , James F. McMillan , Alex D. Williams , Chee Wei Wong

he properties of excitons formed in spherical quantum dots are studied using the $\mathbf{k}\cdot\mathbf{p}$ method within the Hartree approximation. The spherical quantum dots considered have a central core and several concentric layers of…

Mesoscale and Nanoscale Physics · Physics 2019-10-11 Mariano Garagiola , Omar Osenda

The nanostructure of hydrogenated amorphous silicon (a Si:H) is studied by a combination of small-angle X-ray (SAXS) and neutron scattering (SANS) with a spatial resolution of 0.8 nm. The a-Si:H materials were deposited using a range of…

Materials Science · Physics 2020-11-04 Eike Gericke , Jimmy Melskens , Robert Wendt , Markus Wollgarten , Armin Hoell , Klaus Lips

Motivated by theoretical predictions that spatially complex concentration modulations of Si and Ge can increase the valley splitting in quantum wells, we grow and characterize Si/SiGe heterostructures with a thin, pure Ge layer at the top…

A simple model of circular polarization dependence on Mn delta-layer position in LED heterostructures with InGaAs/GaAs quantum well is proposed, being able to explain quite accurately recent fascinating experimental results [S.V. Zaitsev,…

Mesoscale and Nanoscale Physics · Physics 2009-02-23 D. V. Khomitsky