2018-12-12, Feng, Yuyi, Kemmer, Tobias, Graus, Philipp, Nemitz, Clayton A., Boneberg, Johannes, Huang, Lingling, Liu, Juan, Wang, Yongtian, Schmidt-Mende, Lukas, Leiderer, Paul

Metallic nanorod metamaterials, arrays of vertically aligned nanorods embedded in an alumina matrix (diameter ~80 nm, length 100-250 nm, period ~113 nm), have recently emerged as a flexible platform for applications in photonics, opto-electronics and sensing. The optical constants for these nanostructured materials are directly associated with their crystallinity. Controlling the crystallinity of these metamaterials in a fast manner has presented a new challenge. Here we show a laser annealing with a pulsed Nd:YAG laser (λ = 532 nm, FWHM 15 ns) to rapidly change the crystallinity of the metallic nanorods. The small column X-Ray diffraction characterization shows that not only the crystallinity of the metallic nanorods is changed, but also that evaporation of the metal occurs with laser annealing.

2018-11-10, Kemmer, Tobias, Graus, Philipp, Leiderer, Paul, Feng, Yuyi, Nemitz, Clayton, Wang, Yongtian, Boneberg, Johannes, Huang, Lingling, Liu, Juan, Schmidt-Mende, Lukas

Metallic nanorod metamaterials, arrays of vertically aligned nanorods embedded in an alumina matrix (diameter ~80 nm, length 100-250 nm, period ~113 nm), have recently emerged as a flexible platform for applications in photonics, optoelectronics and sensing. The optical constants for these nanostructured materials are directly associated with their crystallinity. Controlling the crystallinity of these metamaterials in a fast manner has presented a new challenge. Here we show a laser annealing with a pulsed Nd:YAG laser (λ = 532 nm, FWHM 15 ns) to rapidly change the crystallinity of the metallic nanorods. The small column X-Ray diffraction characterization shows that not only the crystallinity of the metallic nanorods is changed, but also that evaporation of the metal occurs with laser annealing.

2013, Wehrenfennig, Christian, Palumbiny, Claudia M., Schmidt-Mende, Lukas, Johnston, Michael B., Snaith, Henry J., Herz, Laura M.

We studied charge transport in anodized TiO₂ nanotubes in the context of their application in dye-sensitized solar cells. Optical-pump-THz-probe spectroscopy revealed short free carrier lifetimes of about 15-30 ps, which we attribute to shallow trapping.