%0 Journal Article
%T Far-Infrared Excitations below the Kohn Mode: Internal Motion in a Quantum Dot
%A Roman Krahne
%A Vidar Gudmundsson
%A Christian Heyn
%A Detlef Heitmann
%J Physics
%D 2001
%I arXiv
%R 10.1103/PhysRevB.63.195303
%X We have investigated the far-infrared response of quantum dots in modulation doped GaAs heterostructures. We observe novel modes at frequencies below the center-of-mass Kohn mode. Comparison with Hartree-RPA calculations show that these modes arise from the flattened potential in our field-effect confined quantum dots. They reflect pronounced relative motion of the charge density with respect to the center-of-mass.
%U http://arxiv.org/abs/cond-mat/0102005v1