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

The optical spin orientation and subsequent dynamic nuclear polarization (DNP) in individual self-assembled InGaAs/GaAs quantum dots doped by a single Mn atom is shown to be strongly perturbed by the exchange interaction between a photo-created electron and the spin of the magnetic impurity. The anisotropic part of the exchange, if strong enough, significantly depolarizes the electron spin in moderate magnetic fields, preventing thus any DNP. Yet, for small …

Flexible nitride nanowires light emitting diodes

Presently, flexible light sources mainly use organic materials integrated on lightweight and flexible plastic substrates. However, organic LEDs present a much lower luminance and a shorter lifetime in comparison to the LEDs based on inorganic nitride semiconductors. The inorganic semiconductor devices in their bulk form are mechanically rigid. Polymer-embedded nanowires (NWs) offer an elegant solution to create flexible optoelectronic devices, which combine the high efficiency and the long lifetime …