- Type I band alignment in GaAs 81 Sb 19 /GaAs core-shell nanowires doi link

Auteur(s): Xu T., Wei M., CAPIOD P., Díaz Álvarez A., Han X., Troadec D., Nys P., Berthe M., Lefebvre-Tournier I., Patriarche G., Plissard Sébastien, Caroff P., Ebert Ph., Grandidier B.

(Article) Publié: Applied Physics Letters, vol. 107 p.112102 (2015)

Ref HAL: hal-01713079_v1
DOI: 10.1063/1.4930991

The composition and band gap of the shell that formed during the growth of axial GaAs/GaAs81Sb19/ GaAs heterostructure nanowires have been investigated by transmission electron microscopy combined with energy dispersion spectroscopy, scanning tunneling spectroscopy, and density functional theory calculations. On the GaAs81Sb19 intermediate segment, the shell is found to be free of Sb (pure GaAs shell) and transparent to the tunneling electrons, despite the (110) biaxial strain that affects its band gap. As a result, a direct measurement of the core band gap allows the quantitative determination of the band offset between the GaAs81Sb19 core and the GaAs shell and identifies it as a type I band alignment.