Electrical control of a single Mn atom in a quantum dot

We report on the reversible electrical control of the magnetic properties of a single Mn atom in an individual quantum dot. Our device permits us to prepare the dot in states with three different electric charges, 0, +1e, and -1e which result in dramatically different spin properties, as revealed by photoluminescence. Whereas in the neutral configuration the quantum dot is paramagnetic, the electron-doped dot spin states are spin rotationally invariant and the hole-doped dot spins states are quantized along the growth direction.This work is supported by ANR-France Contract MOMES. J. F.-R. acknowledges funding from MECSpain (Grants No. FIS200402356 and Ramon y Cajal) and from Generalitat Valenciana (No. GV05-152)