A Hubbard model including coupling to leads is used to study the tunneling current of the quantum dot array (QDA) system as a function of the gate voltage. It is found that, due to the weak interdot coupling and strong Coulomb repulsion, a ferromagnetic phase exists in the QDA within a window of the gate voltage. Therefore a QDA may be used as a spin filter to provide a spin-polarized current source.
|Number of pages||6|
|Journal||Chinese Journal of Physics|
|State||Published - Jun 2004|