Excitation spectra of two-dimensional bounded electronic systems in a strong magnetic field

Results concerning the excitation spectra of bounded two-dimensional electronic systems in a strong magnetic field are discussed. The cases of a single quantum dot, a layered dot array, a two-dimensional dot lattice, and a dot with variable Landau level occupations are analyzed. The confining potential is systematically taken into account in phenomenological and microscopic approaches. In the framework of microscopic theory, diagrams having the same order of dimensionless parameter of the problem are summed (i.e. generalized random phase approximation is applicable). The nature of excitations is discussed. The excitation energy consists mainly of the contribution of drift along the edge of the system, plasma oscillations and exciton effects. The results can be applied to describe quantum dots, electrons in a random potential or a system with various filling factors.