Magnetic interaction between coupled quantum dots
University of Jyväskylä, Physics Department, PO Box 35, 40351 Jyväskylä, Finland
Revised: 1 June 1999
Published online: 15 February 2000
We study the magnetic coupling in artificial molecules composed of two and four laterally coupled quantum dots. The electronic ground-state configurations of such systems are determined by applying current spin density functional theory which allows to include effects of magnetic fields. While the ground-state of a two-dot molecule with strong enough inter-dot coupling tends to be antiferromagnetic with respect to the spins of the single dot components, we find that a square lattice of four dots has a ferromagnetic ground state.
PACS: 71. – Electronic structure / 73.20.Dx – Electron states in low-dimensional structures (superlattices, quantum well structures and multilayers) / 85.30.Vw – Low-dimensional quantum devices (quantum dots, quantum wires etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000