Semiconductor nanowires, which are characterized by high crystallinity, polarization anisotropy, and high optical nonlinearity, show great promise as nanoscale building blocks for nanophotonic devices . The development of new noninvasive techniques for scrutinizing individual nanowires, preferably in their native growth environment, is therefore highly desirable. Although the growth occurs in the vertical direction, most work up to date has studied nanowires that have been detached and lie on a substrate. They can then be excited by conventional optical fields with detection of scattered signals along the substrate normal. The use of second-harmonic generation (SHG) has been shown to be very valuable for studying semiconductor assemblies due to its inherent sensitivity to structural symmetry. In order to use SHG to study vertically aligned nanowires, it is essential to tailor the excitation field so that the nanowire is illuminated with polarization along its long axis. This can be done by exciting the nanostructures at normal incidence using the longitudinal field that arises from focused radial polarization [2,3]. Here, we demonstrate that vertically aligned semiconductor nanowires, as grown on top of a semiconductor substrate, can be characterized by SHG with such focused vector beams .
|Title of host publication||European Conference on Lasers and Electro-Optics, CLEO 2015|
|Publication status||Published - 21 Jul 2014|
|MoE publication type||A4 Article in a conference publication|
|Event||European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference - Munich, Germany|
Duration: 21 Jun 2015 → 25 Jun 2015
|Name||Optics InfoBase Conference Papers|
|Conference||European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference|
|Period||21/06/2015 → 25/06/2015|
Bautista, G., Mäkitalo, J., Chen, Y., Dhaka, V., Grasso, M., Karvonen, L., ... Kauranen, M. (2014). Nonlinear imaging of vertically aligned semiconductor nanowires using focused vector beams. In European Conference on Lasers and Electro-Optics, CLEO 2015 (Optics InfoBase Conference Papers).