Temperature dependence of Coulomb oscillations in a few-layer two-dimensional WS2 quantum dot

Xiang-Xiang Song, Zhuo-Zhi Zhang, Jie You, Di Liu, Hai-Ou Li, Gang Cao, Ming Xiao, Guo-Ping Guo

Published 2015-10-13Version 1

Standard semiconductor fabrication techniques are used to fabricate a quantum dot (QD) made of WS2, where Coulomb oscillations were found. The full-width-at-half-maximum of the Coulomb peaks increases linearly with temperature while the height of the peaks remains almost independent of temperature, which is consistent with standard semiconductor QD theory. Unlike graphene etched QDs, where Coulomb peaks belonging to the same QD can have different temperature dependences, these results indicate the absence of the disordered confining potential. This difference in the potential-forming mechanism between graphene etched QDs and WS2 QDs may be the reason for the larger potential fluctuation found in graphene QDs.