Abstract-Probing many-body quantum states in single InAs quantum dots: Terahertz and tunneling spectroscopy

Y. Zhang, K. Shibata, N. Nagai, C. Ndebeka-Bandou, G. Bastard, and K. Hirakawa

http://journals.aps.org/prb/accepted/b8078Yb4Od713559716d61d251bd5c8b07d044ae4

We have investigated the manybody quantum states in single InAs quantum dots by simultaneously obtaining the terahertz (THz) intersublevel transition and single electron tunneling spectra. It is found that the intersublevel transition energies measured in the few-electron region are systematically larger than the excited state (ES) energies determined from the transport measurements. We show that the tunneling and THz spectroscopy probe the same manybody excited states in the QDs, but their sensitivities depend on their selection rules. In the many-electron region, we observe THz peaks whose energies coincide with the tunneling ESs.