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Related papers: Exciton Footprint of Self-assembled AlGaAs Quantum…

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Nanowires are versatile nanostructures, which allow an exquisite control over bandgap energies and charge carrier dynamics making them highly attractive as building blocks for a broad range of photonic devices. For optimal solutions…

Mesoscale and Nanoscale Physics · Physics 2019-10-09 Muhammad Usman

We present an original approach to fabricate single GaAs/AlGaAs core-shell nanowire with robust and reproducible transport properties. The core-shell structure is buried in an insulating GaAs overlayer and connected as grown in a two probe…

Axially-stacked quantum dots (QDs) in nanowires (NWs) have important applications in fabricating nanoscale quantum devices and lasers. Although their performances are very sensitive to crystal quality and structures, there is relatively…

Epitaxially-grown semiconductor quantum dots (QDs) provide an attractive platform for the development of deterministic sources of high-quality quantum states of light. Such non-classical light sources are essential for quantum information…

Mesoscale and Nanoscale Physics · Physics 2023-08-30 Lucie Leguay , Abhiroop Chellu , Joonas Hilska , Esperanza Luna , Andrei Schliwa , Mircea Guina , Teemu Hakkarainen

In a charge tunable device, we investigate the fine structure splitting of neutral excitons in single long-wavelength (1.1\mu m < \lambda < 1.3 \mu m) InGaAs quantum dots as a function of external uniaxial strain. Nominal fine structure…

GaAs nanowires and GaAs-Fe3Si core-shell nanowire structures were grown by molecular-beam epitaxy on oxidized Si(111) substrates and characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Ga droplets were…

Materials Science · Physics 2015-12-10 Bernd Jenichen , Maria Hilse , Jens Herfort , Achim Trampert

Epitaxial III-V semiconductor quantum dots in nanopthonic structures are promising candidates for implementing on-demand indistinguishable single-photon emission in integrated quantum photonic circuits. Quantum dot proximity to the etched…

The realization of reliable single photon emitters operating at high temperature and located at predetermined positions still presents a major challenge for the development of solid-state systems for quantum light applications. We…

We report quantum dots fabricated on very shallow 2-dimensional electron gases, only 30 nm below the surface, in undoped GaAs/AlGaAs heterostructures grown by molecular beam epitaxy. Due to the absence of dopants, an improvement of more…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 W. Y. Mak , F. Sfigakis , K. Das Gupta , O. Klochan , H. E. Beere , I. Farrer , J. P. Griffiths , G. A. C. Jones , A. R. Hamilton , D. A. Ritchie

We study the collective excitations and inelastic light scattering cross-section of an electron gas confined in a GaAs/AlGaAs coaxial quantum well. These system can be engineered in a core-multi-shell nanowire and inherit the hexagonal…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Miquel Royo , Andrea Bertoni , Guido Goldoni

Quantum dots are both excellent single-photon sources and hosts for single spins. This combination enables the deterministic generation of Raman-photons -- bandwidth-matched to an atomic quantum-memory -- and the generation of photon…

Non-classical photon sources made of semiconductor quantum dots (QDs) emitting in the telecommunication C-band are crucial components for low-loss, long-distance photonic quantum communication networks. Here we designed and fabricated…

We demonstrate an efficient core-shell GaAs/AlGaAs nanowire photodetector operating at room temperature. The design of this nanoscale detector is based on a type-I heterostructure combined with a metal-semiconductor-metal (MSM) radial…

Mesoscale and Nanoscale Physics · Physics 2016-01-20 X. Dai , S. Zhang , Z. Wang , G. Adamo , H. Liu , Y. Huang , C. Couteau , C. Soci

Physical implementations of large-scale quantum processors based on solid-state platforms benefit from realizations of quantum bits positioned in regular arrays. Self-assembled quantum dots are well-established as promising candidates for…

A transition from a cylindrical quantum dot to a highly elongated quantum dash is theoretically studied here with an atomistic approach combining empirical tight binding for single particle states and configuration interaction method for…

Mesoscale and Nanoscale Physics · Physics 2019-05-08 Michał Zieliński

We probe the electron transport properties in the shell of GaAs/In0.2Ga0.8As core/shell nanowires at high electric fields using optical pump / THz probe spectroscopy with broadband THz pulses and peak electric fields up to 0.6 MV/cm. The…

Mesoscale and Nanoscale Physics · Physics 2020-06-24 Rakesh Rana , Leila Balaghi , Ivan Fotev , Harald Schneider , Manfred Helm , Emmanouil Dimakis , Alexej Pashkin

A study of previously overlooked structural and optical properties of InGaAs heterostructures grown on (111)B oriented GaAs substrates patterned with inverted 7.5 um pitch pyramidal recesses is presented. First, the composition of the…

Polarization-resolved single dot spectroscopy performed on (211)B InAs/GaAs quantum dots reveals that the fine structure splitting of the excitonic levels in these dots is much lower compared to the usual (100)-grown InAs dots.…

We investigate from first principles the electronic and optical properties of edge-modulated armchair graphene nanoribbons, including both quasi-particle corrections and excitonic effects. Exploiting the oscillating behavior of the ribbon…

Materials Science · Physics 2011-04-19 Deborah Prezzi , Daniele Varsano , Alice Ruini , Elisa Molinari

Achieving uniform nanowire size, density, and alignment across a wafer is challenging, as small variations in growth parameters can impact performance in energy harvesting devices like solar cells and photodetectors. This study demonstrates…