Abstract
Artificial molecules are studied using coupled quantum-dot (QD) ensembles and single QD spectroscopy. We demonstrate a significant improvement in the uniformity of the macroscopic ensembles of vertically self-aligned stacked QDs. The coupling strength between the zero-dimensional states is varied by changing the distance between two layers of stacked self-assembled InAs/GaAs QDs. For strongly coupled QDs grown with a 4 nm spacer layer, state filling spectroscopy reveals a shift of the QD symmetric state to lower energies by ∼23 meV. The wetting layer states are also strongly coupled because of their shallower confinement. Spectra of single pairs of coupled QDs are compared to those of single QDs. Energy level splittings larger than 30 meV of the symmetric and antisymmetric states of the lowest confined shell are measured and compared with theory.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
