Far infrared absorption in triangular and square quantum dots: characterization of corner and side modes

The far-infrared absorption of triangular and square two-dimensional quantum dots is studied by means of time simulations of the density oscillations within the time-dependent local-spin-density approximation. The absorption is spatially analyzed using a local-response theory that allows the identification of {\em corner} and {\em side} modes in the geometric nanostructures. The evolution with a vertical magnetic field of varying intensity is also discussed.