Fractional oscillations of electronic states in a quantum ring
Theoretical Physics, University of Oulu - FIN-90570 Oulu, Finland
2 Max-Planck-Institut für Physik Komplexer Systeme, Außenstelle Stuttgart, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
Accepted: 15 October 1996
We have studied the energy states and the optical-absorption spectra for interacting electrons in a quantum ring with the spin degrees of freedom included. We observe features unique to the spin and interactions viz decrease of the period and amplitude of oscillations of the ground-state energy (fractional Aharonov-Bohm effect). This period decrease is explained in terms of the lifting of spin singlet-triplet degeneracy due to the interactions and Hund's rule. The optical-absorption spectra also show several unique features which are a combined effect of spin, impurity and interactions.
PACS: 73.20.Dx – Electron states in low-dimensional structures (including quantum wells, super lattices, layer structures, and intercalation compounds) / 71.45.Gm – Exchange, correlation, dielectric and magnetic functions, plasmons / 73.20.Mf – Collective excitations (including plasmons and other charge-density excitations)
© EDP Sciences, 1996