Steinebach, Christoph and Schüller, Christian and Biese, G. and Heitmann, Detlef and Eberl, Karl
Observation of finite-thickness effects on the spin-density excitations in quantum wires.
Physical Review B (PRB) 57 (3), pp. 1703-1706.
Other URL: http://link.aps.org/doi/10.1103/PhysRevB.59.10240
We investigate the effect of finite thickness of quantum wires on spin-density excitations (SDEs). In contrast to plasmon excitations, SDEs depend sensitively on the force law that describes the electron-electron interaction. We find that, especially for low electron densities, the corrections due to a three-dimensional interaction are very important. We use both the time-dependent Hartree-Fock and local-density approximations to calculate the first confined collective SDE. The results are compared with Raman experiments. The agreement is excellent and shows that a three-dimensional treatment is absolutely necessary to explain the experiments.