Precise Determination of the Crystallographic Orientations
in Single ZnS Nanowires by Second-Harmonic Generation Microscopy
- Publication date
- Publisher
Abstract
We
report on the systematical study of the second-harmonic generation
(SHG) in single zinc sulfide nanowires (ZnS NWs). The high-quality
ZnS NWs with round cross-section were fabricated by chemical vapor
deposition method. The transmission electron microscopy images show
that the actual growth axis has a deviation angle of 0°∼20°
with the preferential growth direction [120], which leads to the various
polarization-dependent SHG response patterns in different individual
ZnS NWs. The SHG response is quite sensitive to the orientations of <i>c</i> axis as well as the (100) and (010) crystal-axis of ZnS
NWs; thus, all the three crystal-axis orientations of ZnS NWs are
precisely determined by the SHG method. A high SHG conversion efficiency
of 7 × 10<sup>–6</sup> is obtained in single ZnS NWs,
which shows potential applications in nanoscale ultraviolet light
source, nonlinear optical microscopy, and nanophotonic devices