Academic Journal

Surface effects of vapour-liquid-solid driven Bi surface droplets formed during molecular-beam-epitaxy of GaAsBi

التفاصيل البيبلوغرافية
العنوان: Surface effects of vapour-liquid-solid driven Bi surface droplets formed during molecular-beam-epitaxy of GaAsBi
المؤلفون: Steele, J. A., Lewis, R. A., Horvat, J., Nancarrow, M. J. B., Henini, M., Fan, D., Mazur, Y. I., Schmidbauer, M., Ware, M. E., Yu, S.-Q., Salamo, G. J.
المصدر: Scientific Reports ; volume 6, issue 1 ; ISSN 2045-2322
بيانات النشر: Springer Science and Business Media LLC
سنة النشر: 2016
الوصف: Herein we investigate a (001)-oriented GaAs 1− x Bi x /GaAs structure possessing Bi surface droplets capable of catalysing the formation of nanostructures during Bi-rich growth, through the vapour-liquid-solid mechanism. Specifically, self-aligned “nanotracks” are found to exist trailing the Bi droplets on the sample surface. Through cross-sectional high-resolution transmission electron microscopy the nanotracks are revealed to in fact be elevated above surface by the formation of a subsurface planar nanowire, a structure initiated mid-way through the molecular-beam-epitaxy growth and embedded into the epilayer, via epitaxial overgrowth. Electron microscopy studies also yield the morphological, structural and chemical properties of the nanostructures. Through a combination of Bi determination methods the compositional profile of the film is shown to be graded and inhomogeneous. Furthermore, the coherent and pure zincblende phase property of the film is detailed. Optical characterisation of features on the sample surface is carried out using polarised micro-Raman and micro-photoluminescence spectroscopies. The important light producing properties of the surface nanostructures are investigated through pump intensity-dependent micro-PL measurements, whereby relatively large local inhomogeneities are revealed to exist on the epitaxial surface for important optical parameters. We conclude that such surface effects must be considered when designing and fabricating optical devices based on GaAsBi alloys.
نوع الوثيقة: article in journal/newspaper
اللغة: English
DOI: 10.1038/srep28860
الاتاحة: http://dx.doi.org/10.1038/srep28860
https://www.nature.com/articles/srep28860
https://www.nature.com/articles/srep28860.pdf
Rights: https://creativecommons.org/licenses/by/4.0 ; https://creativecommons.org/licenses/by/4.0
رقم الانضمام: edsbas.18402BCA
قاعدة البيانات: BASE