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Wave-vector dependence of spin and density multipole excitations in quantum dots

Manuel Barranco·Leonardo Colletti·Agusti Emperador·Enrico Lipparini·Marti Pi·Llorens Serra
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Abstract

We have employed time-dependent local-spin density functional theory to analyze the multipole spin and charge density excitations in GaAs-AlGaAs quantum dots. The on-plane transferred momentum degree of freedom has been taken into account, and the wave-vector dependence of the excitations is discussed. In agreement with previous experiments, we have found that the energies of these modes do not depend on the transferred wave-vector, although their intensities do. Comparison with a recent resonant Raman scattering experiment [C. Schüller et al, Phys. Rev. Lett {\bf 80}, 2673 (1998)] is made. This allows to identify the angular momentum of several of the observed modes as well as to reproduce their energies.

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Manuel Barranco, Leonardo Colletti, Agusti Emperador, Enrico Lipparini, Marti Pi, Llorens Serra. 1999-07-21. Wave-vector dependence of spin and density multipole excitations in quantum dots. https://doi.org/10.1103/physrevb.61.8289

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