Bipolar spin filter in a quantum dot molecule
arXiv:cond-mat/0602403 · doi:10.1063/1.2175487
Abstract
We show that the tunable hybridization between two lateral quantum dots connected to non-magnetic current leads in a `hanging-dot' configuration that can be used to implement a bipolar spin filter. The competition between Zeeman, exchange interaction, and interdot tunneling (molecular hybridization) yields a singlet-triplet transition of the double dot {\it ground state} that allows spin filtering in Coulomb blockade experiments. Its generic nature should make it broadly useful as a robust bidirectional spin polarizer.
5 pages, 3 figures (to appear in Appl. Phys. Lett.)