Grenoble High Magnet Field Laboratory

Grenoble, France

Grenoble High Magnet Field Laboratory

Grenoble, France

Time filter

Source Type

Galvo Gobato Y.,Federal University of São Carlos | Galeti H.V.A.,Federal University of São Carlos | Dos Santos L.F.,Federal University of São Carlos | Lpez-Richard V.,Federal University of São Carlos | And 10 more authors.
Applied Physics Letters | Year: 2011

We have investigated the polarized-resolved photoluminescence from the contact layers and the quantum-well in an n-type GaAs/GaAlAs resonant tunneling diode for magnetic fields up to 19 T. The optical emission from the GaAs contact layers comprises the recombination from highly spin-polarized two-dimensional electron and hole gases with free tunneling carriers. Both the energy position and intensity of this indirect recombination are voltage-dependent and show remarkably abrupt variations near scattering-assisted tunneling resonances. Our results show that these two dimensional gases act as spin-polarized sources for carriers tunneling through the well in resonant tunneling diodes. © 2011 American Institute of Physics.


Galeti H.V.A.,Federal University of São Carlos | Galvao Gobato Y.,Federal University of São Carlos | Gordo V.O.,Federal University of São Carlos | Dos Santos L.F.,Federal University of São Carlos | And 10 more authors.
Semiconductor Science and Technology | Year: 2012

We have studied the polarized emission from the contact layers and the quantum well of asymmetric n-type GaAs/GaAlAs resonant tunneling diodes under high magnetic fields (up to 19 T) parallel to the tunnel current. The photoluminescence from the GaAs contact layers shows evidence of the recombination from a two-dimensional hole gas accumulated next to the GaAlAs barrier and free carriers. Both the energy position and the intensity of this emission are voltage dependent. In addition, the photoluminescence from the two-dimensional hole gas and quantum well is strongly spin-polarized under the applied voltage and high magnetic fields. Pronounced oscillatory features are observed in the magnetic field dependence of the polarization degree from the quantum well and the two-dimensional hole emissions at integer filling factors. The obtained data show that resonant tunneling diodes are interesting systems to study the physical properties of voltage-controlled two-dimensional gases in the accumulation layers and quantum well. © 2012 IOP Publishing Ltd.


Santos L.F.D.,Federal University of São Carlos | Gobato Y.G.,Federal University of São Carlos | Teodoro M.D.,Federal University of São Carlos | Lopez-Richard V.,Federal University of São Carlos | And 9 more authors.
Nanoscale Research Letters | Year: 2011

We have investigated the polarization-resolved photoluminescence (PL) in an asymmetric n-type GaAs/AlAs/GaAlAs resonant tunneling diode under magnetic field parallel to the tunnel current. The quantum well (QW) PL presents strong circular polarization (values up to -70% at 19 T). The optical emission from GaAs contact layers shows evidence of highly spin-polarized two-dimensional electron and hole gases which affects the spin polarization of carriers in the QW. However, the circular polarization degree in the QW also depends on various other parameters, including the g-factors of the different layers, the density of carriers along the structure, and the Zeeman and Rashba effects. © 2011 dos Santos et al.

Loading Grenoble High Magnet Field Laboratory collaborators
Loading Grenoble High Magnet Field Laboratory collaborators