Exchange interaction-driven dynamic nuclear polarization in Mn-doped InGaAs/GaAs quantum dots

Abstract

We investigated optical spin orientation and dynamic nuclear polarization (DNP) in individual self-assembled InGaAs/GaAs quantum dots (QDs) doped by a single Mn atom, a magnetic impurity providing a neutral acceptor A${}^0$ with an effective spin $J=1$. We find that the spin of an electron photo-created in such a quantum dot can be efficiently oriented by a quasi-resonant circularly-polarized excitation. For the electron spin levels which are made quasi-degenerate by a magnetic field compensating the exchange interaction ${\Delta }_e$ with A${}^0$, there is however a full depolarization due the anisotropic part of the exchange. Still, in most studied QDs, the spin polarized photo-electrons give rise to a pronounced DNP which grows with a longitudinal magnetic field until a critical field where it abruptly vanishes. For some QDs, several replica of such DNP sequence are observed at different magnetic fields. This striking behavior is qualitatively discussed as a consequence of different exchange interactions experienced by the electron, driving the DNP rate via the energy cost of electron-nucleus spin flip-flops.

10 pages, 7 figures

References in corpus (23)

• Nuclear spin physics in quantum dots: an optical investigation
• Optical manipulation of a single Mn spin in a CdTe-based quantum dot
• Optical spin orientation of a single manganese atom in a quantum dot
• Optically probing the fine structure of a single Mn atom in an InAs quantum dot
• Nuclear Spin Switch in Semiconductor Quantum Dots
• Designing quantum dots for solotronics
• Dynamic nuclear polarization of a single charge-tunable InAs/GaAs quantum dot
• Bistability of the Nuclear Polarisation created through optical pumping in InGaAs Quantum Dots
• Direct measurement of the hole-nuclear spin interaction in single quantum dots
• Nonlinear dynamics of quantum dot nuclear spins
• Geometrical effects on the optical properties of quantum dots doped with a single magnetic atom
• Isotope sensitive measurement of the hole-nuclear spin interaction in quantum dots
• Pumping of nuclear spins by the optical solid effect in a quantum dot
• Optical Stark Effect and Dressed Excitonic States in a Mn-doped Quantum Dot
• Optical initialization, readout and dynamics of a Mn spin in a quantum dot
• Brightening of dark excitons in a single quantum dot containing a single magnetic ion
• Magnetic anisotropy of singly Mn-doped InAs/GaAs quantum dots
• Optical control of the spin state of two Mn atoms in a quantum dot
• Optical pumping and non-destructive readout of a single magnetic impurity spin in an InAs/GaAs quantum dot
• Quantum interference in exciton-Mn spin interactions in a CdTe semiconductor quantum dot
• Radiative cascades in charged quantum dots
• General theory of feedback control of a nuclear spin ensemble in quantum dots
• Optical properties of charged quantum dots doped with a single magnetic impurity

Cited by in corpus (1)

• Readout of a dopant spin in the anisotropic quantum dot with a single magnetic ion