@Article{AlHassan_nt_2020,
  author    = {Al Hassan, Ali and L\"ahnemann, Jonas and Leake, Steven and K\"upers, Hanno and Niehle, Michael and Bahrami, Danial and Bertram, Florian and Lewis, Ryan B. and Davtyan, Arman and Schuelli, Tobias and Geelhaar, Lutz and Pietsch, Ullrich},
  title     = {Spatially-resolved luminescence and crystal structure of single core-shell nanowires measured in the as-grown geometry},
  journal   = {Nanotechnology},
  year      = {2020},
  volume    = {31},
  number    = {21},
  pages     = {214002},
  month     = feb,
  abstract  = {We report on the direct correlation between the structural and optical properties of single, as-grown core-multi-shell GaAs/In0.15Ga0.85As/GaAs/AlAs/GaAs nanowires. Fabricated by molecular beam epitaxy on a pre-patterned Si(111) substrate, on a row of well separated nucleation sites, it was possible to access individual nanowires in the as-grown geometry. The polytype distribution along the growth axis of the nanowires was revealed by synchrotron-based nanoprobe X-ray diffraction techniques monitoring the axial 111 Bragg reflection. For the same nanowires, the spatially-resolved emission properties were obtained by cathodoluminescence hyperspectral linescans in a scanning electron microscope. Correlating both measurements, we reveal a blueshift of the shell quantum well emission energy combined with an increased emission intensity for segments exhibiting a mixed structure of alternating wurtzite and zincblende stacking compared with the pure crystal polytypes. The presence of this mixed structure was independently confirmed by cross-sectional transmission electron microscopy.},
  arxiv     = {2002.08172},
  doi       = {10.1088/1361-6528/ab7590},
}