Abstract
We have investigated the effect of In-Ga intermixing on the electronic states in single self-assembled InAs quantum dots (QDs) coupled to nanogap metallic electrodes. The orbital quantization energies of the QDs and the tunnel resistances exhibited a strong dependence on growth temperature, TG, due to In-Ga intermixing during QD formation. When the intermixing was suppressed by reducing TG to 470 °C, the electron wave functions in the QDs become more extended in space and QD-electrode coupling sufficiently strong to form the Kondo singlet states at 4.3 K was realized even in a small QD of ∼45 nm diameter.
| Original language | English |
|---|---|
| Article number | 162107 |
| Journal | Applied Physics Letters |
| Volume | 94 |
| Issue number | 16 |
| DOIs | |
| State | Published - 2009 |
Bibliographical note
Funding Information:We thank H. Sakaki and Y. Arakawa for continuous encouragement and S. Ishida for technical support. This work was partly supported by the Japan Science and Technology Corporation (CREST), Grants-in-Aid from the Japan Society for the Promotion of Science (Grant Nos. 18201027 and 19560338), a research grant from the Mazda Foundation, and the Specially Coordinated Fund from MEXT (NanoQuine).