B. Eble

Hole–Nuclear Spin Interaction in Quantum Dots

We have measured the carrier spin dynamics in p-doped InAs/GaAs quantum dots by pump-probe and time-resolved photoluminescence experiments. We obtained experimental evidence of the hyperfine interaction between hole and nuclear spins. In the absence of an external magnetic field, our calculations based on dipole-dipole coupling between the hole and the quantum dot nuclei lead to a hole-spin dephasing time for an ensemble of dots of 14 ns, in close agreement with experiments.

Hole–spin dephasing time associated with hyperfine interaction in quantum dots

The spin interaction of a hole confined in a quantum dot with the surrounding nuclei is described in terms of an effective magnetic field. We show that, in contrast to the Fermi contact hyperfine interaction for conduction electrons, the dipole-dipole hyperfine interaction is anisotropic for a hole, for both pure or mixed hole states. We evaluate the coupling constants of the hole-nuclear interaction and demonstrate that they are only 1 order of magnitude smaller than the coupling constants of the electron-nuclear interaction. We also study, theoretically, the hole-spin dephasing of an ensemble of quantum dots via the hyperfine interaction in the framework of frozen fluctuations of the nuclear field, in the absence or in the presence of an applied magnetic field. We also discuss experiments which could evidence the dipole-dipole hyperfine interaction and give information on hole mixing.

Dynamic nuclear polarization of a single charge-tunable InAs/GaAs quantum dot

We report on the dynamic nuclear polarization of a single charge-tunable self-assembled InAs/GaAs quantum dot in a longitudinal magnetic field of

Bistability of the nuclear polarization created through optical pumping in In 1 − x Ga x As quantum dots

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Monitoring electrically driven cancellation of exciton fine structure in a semiconductor quantum dot by optical orientation

0.2T. The hyperfine interaction between the optically oriented electron and nuclei spins leads to the polarization of the quantum dot nuclei measured by the Overhauser-shift of the singly-charged excitons (

Effects of strain on the optoelectronic properties of annealed InGaAs/GaAs self-assembled quantum dots

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Electron and hole spin cooling efficiency in InAs quantum dots: The role of nuclear field

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Hyperfine interaction in InAs/GaAs self-assembled quantum dots: dynamical nuclear polarization versus spin relaxation

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Optical pumping and reversal of hole spin in InAs/GaAs quantum dots

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Signature of the Overhauser field on the coherent spin dynamics of donor-bound electrons in a single CdTe quantum well

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