Skip to main content

Research Repository

Advanced Search

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

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.


J.A. Steele

R.A. Lewis

J. Horvat

M.J.B. Nancarrow

D. Fan

Y.I. Mazur

M Schmidbauer

M.E. Ware

S.Q. Yu

G.J. Salamo


Herein we investigate a (001)-oriented GaAs1−xBix/GaAs structure possessing Bi surface droplets capable of catalysing the formation of nanostructures during Bi-rich growth, through the vapourliquid-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.


Steele, J., Lewis, R., Horvat, J., Nancarrow, M., Henini, M., Fan, D., …Salamo, G. (in press). Surface effects of vapour-liquid-solid driven Bi surface droplets formed during molecular-beam-epitaxy of GaAsBi. Scientific Reports, 6(28860),

Journal Article Type Article
Acceptance Date Jun 9, 2016
Online Publication Date Jul 5, 2016
Deposit Date Jul 12, 2016
Publicly Available Date Jul 12, 2016
Journal Scientific Reports
Electronic ISSN 2045-2322
Publisher Nature Publishing Group
Peer Reviewed Peer Reviewed
Volume 6
Issue 28860
Public URL
Publisher URL


16_Steele.pdf (2.8 Mb)

Copyright Statement
Copyright information regarding this work can be found at the following address:

You might also like

Downloadable Citations