Scanning tunneling microscope study of capped quantum dots

Song, H. Z.; Kawabe, M.; Okada, Y.; Yoshizaki, R.; Usuki, T.; Nakata, Y.; Ohshima, T.; Yokoyama, N.
September 2004
Applied Physics Letters;9/20/2004, Vol. 85 Issue 12, p2355
Academic Journal
On thinly capped InGaAs/GaAs quantum dots (QDs), a simultaneous study of both the microscopic and electronic structures was carried out using scanning tunneling microscopy (STM). Although the surface is morphologically flat, the STM image of the embedded QDs can be clearly observed at cryogenic temperatures and is distinguishable up to room temperature. Such images are available in a particular bias range, which corresponds to the occurrence of QD-associated current, as demonstrated in scanning tunneling spectroscopy.


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