Figure 5
Absorbance spectra of the Ge NWs depending on the wire length in the Vis-NIR region.
The saturated absorbance was observed in Ge NWs greater than 2.9 μm length at a Ti:sapphire photon energy of 790 nm. Inset shows a photograph of the Ge NWs sample grown vertically with a cone shape of 5.2 and 5.5 μm in length, indicated by the color black.
