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Related papers: Electrical Spin Pumping of Quantum Dots at Room Te…

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We have demonstrated by electroluminescence the injection of spin polarized electrons through Co/Al2O3/GaAs tunnel barrier into p-doped InAs/GaAs quantum dots embedded in a PIN GaAs light emitting diode. The spin relaxation processes in the…

The temperature-dependent electron spin relaxation of positively charged excitons in a single InAs quantum dot (QD) was measured by time-resolved photoluminescence spectroscopy at zero applied magnetic fields. The experimental results show…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 X. M. Dou , B. Q. Sun , D. S. Jiang , H. Q. Ni , Z. C. Niu

We report on efficient spin injection in p-doped InGaAs/GaAs quantum-dot (QD) spin light emitting diode (spin-LED) under zero applied magnetic field. A high degree of electroluminescence circular polarization (Pc) ~19% is measured in…

We present a complete description of spin injection and detection in Fe/Al_xGa_{1-x}As/GaAs heterostructures for temperatures from 2 to 295 K. Measurements of the steady-state spin polarization in the semiconductor indicate three…

Materials Science · Physics 2009-11-10 C. Adelmann , X. Lou , J. Strand , C. J. Palmstrom , P. A. Crowell

We propose a novel scheme to efficiently polarize and manipulate the electron spin in a quantum dot. This scheme is based on the spin-orbit interaction and it possesses following advantages: (1) The direction and the strength of the spin…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Qing-feng Sun , X. C. Xie

The spin polarization of electrons trapped in InAs self-assembled quantum dot ensembles is investigated. A statistical approach for the population of the spin levels allows one to infer the spin polarization from the measure values of the…

Materials Science · Physics 2008-04-04 F. G. G. Hernandez , T. P. Mayer Alegre , G. Medeiros-Ribeiro

We report the room-temperature electroluminescence (EL) with nearly pure circular polarization (CP) from GaAs-based spin-polarized light-emitting diodes (spin-LEDs). External magnetic fields are not used during device operation. There are…

Optics · Physics 2017-07-05 N. Nishizawa , K. Nishibayashi , H. Munekata

The emission of circularly polarized light from a single quantum dot relies on the injection of carriers with well-defined spin polarization. Here we demonstrate single dot electroluminescence (EL) with a circular polarization degree up to…

We demonstrate that non-equilibrium electrons in thin nonmagnetic semiconductor layers or quantum dots can be fully spin polarized by means of simultaneous electrical spin injection and extraction. The complete spin polarization is achieved…

Other Condensed Matter · Physics 2009-11-11 V. V. Osipov , A. G. Petukhov , V. N. Smelyanskiy

We report electronic control and measurement of an imbalance between spin-up and spin-down electrons in micron-scale open quantum dots. Spin injection and detection was achieved with quantum point contacts tuned to have spin-selective…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 E. J. Koop , B. J. van Wees , D. Reuter , A. D. Wieck , C. H. van der Wal

The backscattering process of injected electrons on exchange-splitted levels of quantum well (QW) in ferromagnetic metal / insulator / semiconductor heterostructure is studied. It is found that, if one of the exchange-splitted levels lies…

Mesoscale and Nanoscale Physics · Physics 2014-06-20 Leonid Lutsev

We report on the spin-polarized electron injection through an Fe(100)/InAs(100) junction. The circularly polarized electroluminescence of injected electrons from epitaxially grown Fe thin film into InAs(100) in an external magnetic field is…

We investigate in micro-photoluminescence experiments the dynamical nuclear polarization in individual InGaAs quantum dots. Experiments carried out in an applied magnetic field of 2T show that the nuclear polarization achieved through the…

Other Condensed Matter · Physics 2009-11-13 B. Urbaszek , P. -F. Braun , X. Marie , O. Krebs , A. Lemaitre , P. Voisin , T. Amand

A quantum dot spin LED provides a test of carrier spin injection into a qubit, as well as a means of analyzing carrier spin injection in general and local spin polarization. The polarization of the observed light is, however, significantly…

Condensed Matter · Physics 2009-11-10 C. E. Pryor , M. E. Flatté

Exciton spin and related optical polarization in self-assembled InAs/In$_{0.53}$Ga$_{0.23}$Al$_{0.24}$As/InP(001) quantum dashes emitting at 1.55 {\mu}m are investigated by means of polarization- and time-resolved photoluminescence, as well…

Mesoscale and Nanoscale Physics · Physics 2018-07-25 M. Syperek , Ł. Dusanowski , M. Gawełczyk , G. Sęk , A. Somers , J. P. Reithmaier , S. Höfling , J. Misiewicz

We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic…

Mesoscale and Nanoscale Physics · Physics 2012-10-23 Szabolcs Csonka , Ireneusz Weymann , Gergely Zarand

Multi-million atom simulations are performed to study stacking-angle ($\theta$) dependent strain profiles, electronic structure, and polarization-resolved optical modes from [110]-tilted quantum dot stacks (QDSs). Our calculations reveal…

Mesoscale and Nanoscale Physics · Physics 2014-03-18 Muhammad Usman

We study spin polarization in a split-gate quantum wire focussing on the effect of a realistic smooth potential due to remote donors. Electron interaction and spin effects are included within the density functional theory in the local spin…

Mesoscale and Nanoscale Physics · Physics 2008-04-04 M. Evaldsson , S. Ihnatsenka , I. V. Zozoulenko

Spin manipulation in coupled quantum dots is of interest for quantum information applications. Control of the exchange interaction between electrons and holes via an applied electric field may provide a promising technique for such spin…

We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 L. P. Rokhinson , L. N. Pfeiffer , K. W. West
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