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InAs quantum wells (QWs) grown on InP substrates are interesting for their applications in devices with high spin-orbit coupling (SOC) and their potential role in creating topologically nontrivial hybrid heterostructures. These QWs rely on…

Mesoscale and Nanoscale Physics · Physics 2025-03-18 C. P. Dempsey , J. T. Dong , I. Villar Rodriguez , Y. Gul , S. Chatterjee , M. Pendharkar , S. N. Holmes , M. Pepper , C. J. Palmstrøm

The coherent spin dynamics of resident carriers, electrons and holes, in semiconductor quantum structures is studied by periodical optical excitation using short laser pulses and in an external magnetic field. The generation and dephasing…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 I. A. Yugova , M. M. Glazov , D. R. Yakovlev , A. A. Sokolova , M. Bayer

Epitaxial ferromagnetic metal - semiconductor heterostructures are investigated using polarization-dependent electroabsorption measurements on GaAs p-type and n-type Schottky diodes with embedded In1-xGaxAs quantum wells. We have conducted…

Condensed Matter · Physics 2009-11-07 A. F. Isakovic , D. M. Carr , J. Strand , B. D. Schultz , C. J. Palmstrom , P. A. Crowell

We introduce the concept of a spintronic effective mass for spin-polarized carriers in semiconductor structures, which arises from the strong spin-polarization dependence of the renormalized effective mass in an interacting spin-polarized…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ying Zhang , S. Das Sarma

A hight degree of spin polarization is achieved for a Mn atom localized in a semiconductor quantum dot using quasi-resonant optical excitation at zero magnetic field. Optically created spin polarized carriers generate an energy splitting of…

Other Condensed Matter · Physics 2012-06-18 C. Le Gall , L. Besombes , H. Boukari , R. Kolodka , H. Mariette , J. Cibert

We investigate the effect of density down-ramps on the acceleration of ions via Magnetic Vortex Acceleration (MVA) in a near-critical density gas target by means of particle-in-cell simulations. The spin-polarization of the accelerated…

Plasma Physics · Physics 2021-05-31 Lars Reichwein , Anna Hützen , Markus Büscher , Alexander Pukhov

Sharp threshold-like transitions between two stable nuclear spin polarizations are observed in optically pumped individual InGaAs self-assembled quantum dots embedded in a Schottky diode when the bias applied to the diode is tuned. The…

Optically addressable spins are actively investigated in quantum communication, processing and sensing. Optical and spin coherence lifetimes, which determine quantum operation fidelity and storage time, are often limited by spin-spin…

A highly asymmetric dynamic nuclear spin pumping is observed in a single self assembled InGaAs quantum dot subject to resonant optical pumping of the neutral exciton transition leading to a large maximum polarization of 54%. This dynamic…

Mesoscale and Nanoscale Physics · Physics 2010-09-30 F. Klotz , V. Jovanov , J. Kierig , E. C. Clark , M. Bichler , G. Abstreiter , M. S. Brandt , J. J. Finley , H. Schwager , G. Giedke

We report on a picosecond-fast optical removal of spin polarization from a self-confined photo-carrier system at an undoped GaAs/AlGaAs interface possessing superior long-range and high-speed spin transport properties. We employed a…

Other Condensed Matter · Physics 2017-10-04 L. Nádvorník , M. Surýnek , K. Olejník , V. Novák , J. Wunderlich , F. Trojánek , T. Jungwirth , P. Němec

We report on the direct measurement of the electron spin splitting and the accompanying nuclear Overhauser (OH) field, and thus the underlying nuclear spin polarization (NSP) and fluctuation bandwidth, in a single InAs quantum dot under…

Mesoscale and Nanoscale Physics · Physics 2021-01-04 Aaron M. Ross , Allan S. Bracker , Michael K. Yakes , Daniel Gammon , L. J. Sham , Duncan G. Steel

We propose a new method for dynamic nuclear polarisation in a quasi one-dimensional quantum wire utilising the spin-orbit interaction, the hyperfine interaction, and a finite source-drain potential difference. In contrast with current…

Mesoscale and Nanoscale Physics · Physics 2008-03-05 V. Tripathi , A. C. H. Cheung , N. R. Cooper

A comparison is made between the degree of spin polarization of electrons excited by one- and two-photon absorption of circularly polarized light in bulk zincblende semiconductors. Time- and polarization-resolved experiments in…

Other Condensed Matter · Physics 2007-05-23 R. D. R. Bhat , P. Nemec , Y. Kerachian , H. M. van Driel , J. E. Sipe , Arthur L. Smirl

Using optical pulses of variable duration up to 80 ps, we report on spin coherence initialization and its subsequent detection in n-type singly-charged quantum dots, subject to a transverse magnetic field, by pump-probe techniques. We…

Mesoscale and Nanoscale Physics · Physics 2012-01-04 S. Spatzek , S. Varwig , M. M. Glazov , I. A. Yugova , D. R. Yakovlev , D. Reuter , A. D. Wieck , M. Bayer

The dynamic polarization of nuclear spins by photoexcited electrons is studied in a high quality GaAs/AlGaAs quantum well. We find a surprisingly high efficiency of the spin transfer from the electrons to the nuclei as reflected by a…

Mesoscale and Nanoscale Physics · Physics 2017-11-15 R. W. Mocek , V. L. Korenev , M. Bayer , M. Kotur , R. I. Dzhioev , D. O. Tolmachev , G. Cascio , K. V. Kavokin , D. Suter

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 propose a pump-probe set-up to analyse the properties of the collective excitation spectrum of a spinor polariton fluid. By using a linear response approximation scheme, we carry on a complete classification of all excitation spectra, as…

Mesoscale and Nanoscale Physics · Physics 2015-02-24 M. Van Regemortel , M. Wouters , F. M. Marchetti

We study the spin polarization of tunneling holes injected from ferromagnetic GaMnAs into a p-doped semiconductor through a tunneling barrier. We obtain an upper limit to the spin injection rate. We find that spin-orbit interaction…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 L. Brey , J. Fernandez-Rossier , C. Tejedor

We formulate an analytical model for vertical-cavity surface-emitting lasers (VCSELs) with injection (pump) of spin-polarized electrons. Our results for two different modes of carrier recombination allow for a systematic analysis of the…

Other Condensed Matter · Physics 2009-11-13 Christian Gothgen , Rafal Oszwaldowski , Athos Petrou , Igor Zutic

Optical spin orientation and depolarization phenomena in semiconductors are of overwhelming importance for the development of spin-optoelectronics. In this paper we employ Ge-based spin-photodiodes to investigate the room temperature…

Mesoscale and Nanoscale Physics · Physics 2021-03-16 C. Rinaldi , M. Cantoni , R. Bertacco