title: Electron spin dynamics in a self-assembled semiconductor quantum dot: the limit of low magnetic fields.
abstract: Using the trion as an optical probe, we uncover novel electron spin dynamics in CdSe/ZnSe Stranski-Krastanov quantum dots. The longitudinal spin lifetime obeys an inverse power law associated with recharging processes in the dot ensemble. No hint at spin-orbit mediated spin relaxation is found. At very weak magnetic fields (< 50 mT), electron spin dynamics related to the hyperfine interaction with the lattice nuclei is uncovered. A strong Knight field gives rise to nuclear ordering and formation of dynamical polarization on a 100-micros time scale under continuous electron spin pumping. The associated spin transients are temperature robust and can be observed up to 100 K.
authors.affiliation: Institut für Physik, Humboldt Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
authors.forename: I A
authors.initials: IA
authors.lastname: Akimov
authors.forename: D H
authors.initials: DH
authors.lastname: Feng
authors.forename: F
authors.initials: F
authors.lastname: Henneberger