Multipole excitations in quantum dots

Abstract

We have employed time-dependent local-spin density theory to analyze the multipole spin and charge density excitations recently found in GaAs-AlGaAs quatum dots [C. Sch\"uller et al, Phys. Rev. Lett {\bf 80}, 2673 (1998)]. The overall agreement between theory and experiment is good, identifying the angular momentum of the modes observed in the experiment. We have found that high multipolarity spin density edge modes originate from interband transitions instead that from intraband transitions, as it happens in the dipole case.