High-temperature spin-polarized quantum dot light-emitting diodes

We believe our demonstration of high-temperature operation in a GaMnAs spin-LED to be an important step in the quest toward room-temperature spin-LED operation. In this paper, we have investigated the properties of Mn-doped InAs quantum dot multilayers grown by LT-MBE. We find that the dilute magnetic quantum dot samples exhibit ferromagnetic behavior at and above room-temperature, possibly resulting from the joint effects of quantum confinement, epitaxial strain, and disorder introduced by the self-organization process. Electron energy loss spectroscopy (EELS) indicates that the Mn atoms incorporate predominantly with the InAs dots. Work is currently underway to incorporate InAs:Mn QDs in the spin-aligner of a spin-LED to demonstrate room-temperature operation; our results are presented.