2003/07/31 by P. Lucignano, B. Jouault, A. Tagliacozzo
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.69.045314
published as Phys.Rev.B 69,045314 (2004) · 9 pages, 9 figures. submitted to Phys.Rev.B
arxiv created 2003/09/12 · arxiv updated 2009/11/30
Coulomb interactions of few ( N ) electrons confined in a disk shaped quantum dot, with a large magnetic field B=B^* applied in the z-direction (orthogonal to the dot), produce a fully spin polarized ground state. We numerically study the splitting of the levels corresponding to the multiplet of total spin S=N/2 (each labeled by a different total angular momentum Jz ) in presence of an electric field parallel to B , coupled to S by a Rashba term. We find that the first excited state is a spin exciton with a reversed spin at the origin. This is reminiscent of the Quantum Hall Ferromagnet at filling one which has the skyrmion-like state as its first excited state. The spin exciton level can be tuned with the electric field and infrared radiation can provide energy and angular momentum to excite it.