Far-infrared spectroscopy of single quantum dots in high magnetic fields

O. Astafiev, V. Antonov, T. Kutsuwa, S. Komiyama
2002 Physical Review B (Condensed Matter)  
Excitation spectra of single GaAs/Al x Ga 1Ϫx As quantum dots ͑QD's͒ are studied by using a technique of far-infrared single-photon detection. The spectra consist of a single resonance line, the resonance frequency of which is by several percent larger than the cyclotron-resonance frequency but is substantially smaller than the magnetoplasma frequencies of mesa-etched QD's earlier found through the standard far-infrared transmission spectroscopy. The resonance frequency is found to be in
more » ... tial agreement with the characteristic frequency of the parabolic bare confinement potential of the QD's, and is ascribed to the excitation of the upper branch of the Kohn-mode collective plasma oscillations.
doi:10.1103/physrevb.65.085315 fatcat:wxlsuqu25vgbpk4bq5hqn5s7ha