224 citations · 1.1k across the 21 of their papers we have counts for
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Nucleation at the phase transition near 40~C in MnAs nanodisks
B Jenichen, Y Takagaki, K H Ploog +3
The phase transition near 40~C of both as-grown thin epitaxial MnAs films prepared by molecular beam epitaxy on GaAs(001) and nanometer-scale disks fabricated from the s…
A microscopic model for the magnetic field driven breakdown of the dissipationless state in the integer and fractional quantum Hall effect
A. Poux, Z. R. Wasilewski, K. J. Friedland +5
Intra Landau level thermal activation, from localized states in the tail, to delocalized states above the mobility edge in the same Landau level, explains the (half width…
Comment on "Identification of different electron screening behavior between the bulk and surface of (Ga,Mn)As [Phys. Rev. Lett. 107, 187203 (2011)]"
M. Moreno, K. H. Ploog
In a recent Letter [Phys. Rev. Lett. 107, 187203 (2011)], Fujii et al. reported Mn 2p photoelectron emission spectra for (Ga,Mn)As recorded using hard x-rays. Due to the enhanced b…
Phase-separated high-temperature-annealed (Ga,Mn)As: A negative charge-transfer-energy material
M. Moreno, K. H. Ploog
The approximate location in the Zaanen-Sawatzky-Allen diagram of the phase-separated (Ga,Mn)As material, consisting of MnAs nanoclusters embedded in GaAs, is determined on the basi…
Enhanced electron correlations, local moments, and Curie temperature in strained MnAs nanocrystals embedded in GaAs
M. Moreno, J. I. Cerdá, K. H. Ploog +1
We have studied the electronic structure of hexagonal MnAs, as epitaxial continuous film on GaAs(001) and as nanocrystals embedded in GaAs, by Mn 2p core-level photoemission spectr…
Quantum effects in linear and non-linear transport of T-shaped ballistic junction
J. Wrobel, P. Zagrajek, M. Czapkiewicz +6
We report low-temperature transport measurements of three-terminal T-shaped device patterned from GaAs/AlGaAs heterostructure. We demonstrate the mode branching and bend resistance…
Phase study of oscillatory resistances in microwave-irradiated- and dark- GaAs/AlGaAs devices: Indications of a new class of integral quantum Hall effect
R. G. Mani, W. B. Johnson, V. Umansky +2
We report the experimental results from a dark study and a photo-excited study of the high mobility GaAs/AlGaAs system at large filling factors, . At large-, the dark study i…
Mesoscopic spin confinement during acoustically induced transport
J. A. H. Stotz, P. V. Santos, R. Hey +1
Long coherence lifetimes of electron spins transported using moving potential dots are shown to result from the mesoscopic confinement of the spin vector. The confinement dimension…
Influence of the single-particle Zeeman energy on the quantum Hall ferromagnet at high filling factors
B. A. Piot, D. K. Maude, M. Henini +10
In a recent paper [B. A. Piot et al., Phys. Rev. B 72, 245325 (2005)], we have shown that the lifting of the electron spin degeneracy in the integer quantum Hall effect at high fil…
Magnetotransport in two-dimensional electron gases on cylindrical surfaces
K. -J. Friedland, R. Hey, H. Kostial +6
We have fabricated high-mobility, two-dimensional electron gases in a GaAs quantum well on cylindrical surfaces, which allows to investigate the magnetotransport behavior under var…
In-plane optical anisotropy due to conduction band electron wavefunctions
J. Łusakowski, M. Sakowicz, K. J. Friedland +2
Photoluminescence measurements were carried out on Be -doped GaAs/AlGaAs heterostructure at 1.6 K in magnetic fields () up to 5 T. Luminescence originating…
Spatial Coherence of a Polariton Condensate
Hui Deng, Glenn S. Solomon, Rudolf Hey +2
We perform Young's double-slit experiment to study the spatial coherence properties of a two-dimensional dynamic condensate of semiconductor microcavity polaritons. The coherence l…
Phase study of oscillatory resistances in high mobility GaAs/AlGaAs devices: Indications of a new class of integral quantum Hall effect
R. G. Mani, W. B. Johnson, V. Umansky +2
An experimental study of the high mobility GaAs/AlGaAs system at large- indicates several distinct phase relations between the oscillatory diagonal- and Hall- resistances, and s…
Quantum Degenerate Exciton-Polaritons in Thermal Equilibrium
H Deng, D Press, S Gotzinger +4
We study the momentum distribution and relaxation dynamics of semiconductor microcavity polaritons by angle-resolved and time-resolved spectroscopy. Above a critical pump level, th…
Magnetophonon resonance in high density, high mobility quantum well systems
C. Faugeras, D. K. Maude, G. Martinez +5
We have investigated the magnetophonon resonance (MPR) effect in a series of single GaAs quantum well samples which are symmetrically modulation doped in the adjacent short period…
The quantum Hall ferromagnet at high filling factors: A magnetic field induced Stoner transition
B. A. Piot, D. K. Maude, M. Henini +7
Spin splitting in the integer quantum Hall effect is investigated for a series of AlGaAs/GaAs heterojunctions and quantum wells. Magnetoresistance measurements are pe…
Spin filtering in a hybrid ferromagnetic-semiconductor microstructure
J. Wróbel, T. Dietl, A. Lusakowski +5
We fabricated a hybrid structure in which cobalt and permalloy micromagnets produce a local in-plane spin-dependent potential barrier for high-mobility electrons at the GaAs/AlGaAs…