Open AccessThree-photon absorption in semiconductor quantum dots: experiment
Author(s) -
Xiaobo Feng,
Yu Long Ang,
Jun He,
Cyrus W. Beh,
Xu He,
Wee Shong Chin,
Wei Ji
Publication year - 2008
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.16.006999
Subject(s) - quantum dot , bohr radius , semiconductor , photon , radius , degenerate energy levels , exciton , absorption (acoustics) , atomic physics , physics , fine structure , optics , molecular physics , materials science , condensed matter physics , optoelectronics , quantum mechanics , computer security , computer science
The four-band model, derived under the effective-mass approximation for cubic semiconductor quantum dots (QDs), is compared with experimental measurements on frequency degenerate three-photon absorption (3PA) in CdSe QDs and ZnS QDs. Qualitatively, the model provides the correct prediction on the magnitude of the 3PA cross-sections, which are in the range from 10(-79) to 10(-77) cm(6)s(2)photon(-2) in the light frequency region of interest. More noticeably, the theoretical conclusion of an increasing tendency in the 3PA cross-sections with increasing dot-size is in agreement with the experiment. The discrepancy is also found for smaller QDs (dot-radius is less than one-third of the exciton Bohr radius), which is attributed to neglecting the mixing among the three valence bands in the theory.