Excited states of ring-shaped (InGa)As quantum dots in a GaAs/ (AlGa)As quantum well
نویسندگان
چکیده
By studying the resonant tunneling of electrons through self-assembled ring-shaped InGa As quantum dots embedded in the quantum well of an AlGa As/GaAs/ AlGa As heterostructure, we find evidence for the existence of excited states of the quantum dots which exhibit a 2pz-like character along the growth direction z. The states are investigated by magnetotunneling spectroscopy with magnetic fields applied parallel and perpendicular to z.
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