Modes of Excitation in Two-Dimensional Quantum Dots

The electronic structures of low-lying excited states of a polarized quantum dot with 6 electrons has been studied. The Hamiltonian has been diagonalized to obtain the eigenstates. All results are extracted from a detailed analysis of wave functions. Six modes were found that lead to distinct excited core-ring structures. As a result, the core or the ring, or both may be excited, different core-ring structures may coexist. Both crystal-like and liquid-like pictures were found. The role of symmetry constraint was found to be important, the angular momenta of the core and the ring are adjusted to meet the requirement of symmetry constraint.