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Related papers: Optical Spectroscopy of the Hole Spin in GaMnAs Ac…

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A self-consistent calculation of the density of states and the spectral density function is performed in a two-dimensional spin-polarized hole system based on a multiple-scattering approximation. Using parameters corresponding to GaMnAs…

Materials Science · Physics 2007-05-23 E. Dias Cabral , M. A. Boselli , A. T. da Cunha Lima , A. Ghazali , I. C. da Cunha Lima

The amount of ionized Mn acceptors in various p-type Mn-doped GaAs epilayers has been evaluated by electrochemical capacitance-voltage measurements, and has been compared systematically with concentrations of incorporated Mn atoms and holes…

Materials Science · Physics 2009-11-10 R. Moriya , H. Munekata

A self-consistent calculation of the electronic properties of GaAlAs:Mn magnetic semiconductor quantum well structures is performed including the Hartree term and the sp-d exchange interaction with the Mn magnetic moments. The spin…

Materials Science · Physics 2009-10-31 A. Ghazali , I. C. da Cunha Lima , M. A. Boselli

We report on optical orientation of Mn^2+ in bulk GaAs under application of weak longitudinal magnetic field (B <= 100 mT). The manganese spin polarization of 25% is directly evaluated using spin flip Raman scattering spectroscopy. The…

Materials Science · Physics 2010-10-08 I. A. Akimov , R. I. Dzhioev , V. L. Korenev , Yu. G. Kusrayev , V. F. Sapega , D. R. Yakovlev , M. Bayer

A self-consistent electronic structure calculation based on the Luttinger-Kohn model is performed on GaMnAs/GaAs multilayers. The Diluted Magnetic Semiconductor layers are assumed to be metallic and ferromagnetic. The high Mn concentration…

Other Condensed Matter · Physics 2009-11-10 S. C. P. Rodrigues , L. M. R. Scolfaro , J. R. Leite , I. C. da Cunha Lima , G. M. Sipahi , M. A. Boselli

An individual Mn acceptor in GaAs is mapped by Cross-sectional Scanning Tunneling Microscopy (X-STM) at room temperature and a strongly anisotropic shape of the acceptor state is observed. An acceptor state manifests itself as a cross-like…

Materials Science · Physics 2007-05-23 A. M. Yakunin , A. Yu. Silov , P. M. Koenraad , J. H. Wolter , W. Van Roy , J. De Boeck

The measurement of the hole density in the ferromagnetic semiconductor Ga$_{1-x}$Mn$_{x}$As is notoriously difficult using standard transport techniques due to the dominance of the anomalous Hall effect. Here, we report the first…

Materials Science · Physics 2009-11-07 M. J. Seong , S. H. Chun , Hyeonsik M. Cheong , N. Samarth , A. Mascarenhas

Growth of GaMnAs by molecular beam epitaxy is typically performed at low substrate temperatures (250C) and high As overpressures leading to the incorporation of excess As and Mn interstitials, which quench optical signals such as…

Materials Science · Physics 2009-09-29 M. Poggio , R. C. Myers , N. P. Stern , A. C. Gossard , D. D. Awschalom

We present a detailed experimental and theoretical analysis of the optical orientation of electron spins in GaAs/AlAs quantum wells. Using time and polarization resolved photoluminescence excitation spectroscopy, the initial degree of…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 S. Pfalz , R. Winkler , T. Nowitzki , D. Reuter , A. D. Wieck , D. Haegele , M. Oestreich

The paper reports optical orientation experiments performed in the narrow GaAs/AlGaAs quantum wells doped with Mn. We experimentally demonstrate a control over the spin polarization by means of the optical orientation via the…

Mesoscale and Nanoscale Physics · Physics 2016-09-02 P. V. Petrov , I. A. Kokurin , Yu. L. Ivanov , N. S. Averkiev , R. P. Campion , B. L. Gallagher , P. M. Koenraad , A. Yu. Silov

We use point contact Andreev reflection spin spectroscopy to measure the transport spin polarization of MnAs epitaxial films grown on (001) GaAs. By analyzing both the temperature dependence of the contact resistance and the phonon spectra…

Strongly Correlated Electrons · Physics 2009-11-10 R. Panguluri , G. Tsoi , B. Nadgorny , S. H. Chun , N. Samarth , I. I. Mazin

The wave function of a hole bound to an individual Mn acceptor in GaAs is spatially mapped by scanning tunneling microscopy at room temperature and an anisotropic, cross-like shape is observed. The spatial structure is compared with that…

We inject spin-polarized electrons from an Fe/MgO tunnel barrier contact into n-type Ge(001) substrates with electron densities 2e16 < n < 8e17 cm-3, and electrically detect the resulting spin accumulation using three-terminal Hanle…

Materials Science · Physics 2012-02-20 A. T. Hanbicki , S. -. F. Cheng , R. Goswami , O. M. J. van `t Erve , B. T. Jonker

The optical properties of Mn-Mg codoped epitaxial GaN were studied. Addition of Mg acceptors quenches the weak manganese-related photoluminescence (PL) band at 1.3 eV in GaN:Mn and a series of sharp PL peaks are observed at 1 eV in codoped…

Materials Science · Physics 2009-11-10 B. Han , R. Y. Korotkov , B. W. Wessels , M. P. Ulmer

The optical spin orientation effect in a GaAs/(Ga,Al)As quantum well containing a high-mobility 2D electron gas was found to be due to spin-polarized minority carriers, the holes. The observed oscillations of both the intensity and…

Mesoscale and Nanoscale Physics · Physics 2016-04-13 A. V. Koudinov , R. I. Dzhioev , V. L. Korenev , V. F. Sapega , Yu. G. Kusrayev

We present a time-resolved optical study of the dynamics of carriers and phonons in Ga_{1-x}Mn_{x}As layers for a series of Mn and hole concentrations. While band filling is the dominant effect in transient optical absorption in…

Materials Science · Physics 2009-11-11 K. J. Yee , D. Lee , X. Liu , W. L. Lim , M. Dobrowolska , J. K. Furdyna , Y. S. Lim , K. G. Yee , D. S. Kim

We investigate the spin-polarization of the ferromagnetic semiconductor (Ga,Mn)As by point contact Andreev reflection spectroscopy. The conductance spectra are analyzed using a recent theoretical model that accounts for momentum- and…

Materials Science · Physics 2011-02-21 S. Piano , R. Grein , C. J. Mellor , K. Vyborny , R. Campion , M. Wang , M. Eschrig , B. L. Gallagher

We report a surprisingly long spin relaxation time of electrons in Mn-doped p-GaAs. The spin relaxation time scales with the optical pumping and increases from 12 ns in the dark to 160 ns upon saturation. This behavior is associated with…

The spin-dependent recombination (SDR) has been observed in GaAs_{1-x}N_{x} (x = 2.1, 2.7, 3.4%) at room temperature. It reveals itself in a decrease of the edge photoluminescence (PL) intensity by more than a factor of 3 when either the…

A method for high-field optically detected nuclear magnetic resonance (ODNMR) is developed sensitive to 10**8 nuclei. Nuclear spin transitions are induced using a radio frequency coil and detected through Faraday rotation spectroscopy.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Poggio , D. D. Awschalom
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