title: A possible solution for charge sensing in vertical double quantum dots.
abstract: We report the observation of a peculiar charge stability diagram of a vertical double quantum dot, where the conventional Coulomb diamond edges have a sawtooth-like shape. This feature could be understood if we assume the formation of a third quantum dot in the semiconductor volume which is supposed to be a part of the source in the standard quantum dot measurement circuit. The size of this additional dot is larger compared to the size of the original ones, thus the charging energy is smaller, but it still exceeds the thermal energy and affects the electron transport through the structure. Since the big dot is coupled to small ones, the observed effect could be utilized for charge detection, which has always been a problem in the case of vertical quantum dots.
authors.affiliation: Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, Republic of China. smhaung.py90g@nctu.edu.tw
authors.forename: S M
authors.initials: SM
authors.lastname: Huang
authors.forename: A O
authors.initials: AO
authors.lastname: Badrutdinov
authors.forename: K
authors.initials: K
authors.lastname: Kono
authors.forename: K
authors.initials: K
authors.lastname: Ono