Open AccessShape and curved surface effect on silicon quantum dots
Author(s) -
Weiqi Huang,
Zhou Nian-Jie,
Jun Yin,
Xiangshui Miao,
Huang Zhong-Mei,
Chen Han-qiong,
Qin Su,
Shirong Liu,
Chao-Jian Qin
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.084205
Subject(s) - quantum dot , silicon , materials science , band gap , condensed matter physics , surface (topology) , molecular physics , facet (psychology) , electronic structure , optoelectronics , physics , geometry , mathematics , psychology , social psychology , personality , big five personality traits
Curviform surface breaks the symmetrical shape of silicon quantum dots on which some bonds can produce localized electronic states in band gap. The calculation results show that the bonding energy and electronic states of silicon quantum dots are different on various curved surfaces, for example, an Si–O–Si bridge bond on curved surface provides the localized levels in band gap and its bonding energy is shallower than that on facet. The red-shifting of PL spectrum on smaller silicon quantum dots can be explained by curved surface effect. Experiments demonstrate that silicon quantum dots are activated for emission due to the localized levels formed in the band gap.