Advanced

Growth and Characterization of Strained and Alloyed Type-II ZnTe/ZnSe Core-Shell Nanocrystals

Fairclough, Simon M.; Tyrrell, Edward J.; Graham, Darren M.; Lunt, Patrick J. B.; Hardman, Samantha J. O.; Pietzsch, Annette LU ; Hennies, Franz LU ; Moghal, Jonathan; Flavell, Wendy R. and Watt, Andrew A. R., et al. (2012) In Journal of Physical Chemistry C 116(51). p.26898-26907
Abstract
We investigate the growth and the physical and optical properties of type-II heterostructured ZnTe/ZnSe colloidal nanocrystals, focusing on the role of the 7% lattice mismatch between the two materials in determining growth homogeneity and band structure. We find that the lattice mismatch between the two materials places limitations on the range of structures that can be grown, and for those in which coherent growth is achieved we present clear evidence that the low bulk modulus ZnTe cores are compressed by the higher modulus ZnSe shells, accentuating the red-shift of the excitonic state with increasing shell thickness. By employing a variety of characterization tools we build a clear picture of the core-shell architecture. We show how... (More)
We investigate the growth and the physical and optical properties of type-II heterostructured ZnTe/ZnSe colloidal nanocrystals, focusing on the role of the 7% lattice mismatch between the two materials in determining growth homogeneity and band structure. We find that the lattice mismatch between the two materials places limitations on the range of structures that can be grown, and for those in which coherent growth is achieved we present clear evidence that the low bulk modulus ZnTe cores are compressed by the higher modulus ZnSe shells, accentuating the red-shift of the excitonic state with increasing shell thickness. By employing a variety of characterization tools we build a clear picture of the core-shell architecture. We show how strain is manifested in structures with sharp core-shell interfaces and how intentional alloying of the interface can influence the growth and exciton energies. We show that a (2,6)-band effective mass model is able to distinguish between the as-grown "sharp" and "alloyed" interfaces, indicating that the alloyed structures incorporate reduced strain. (Less)
Please use this url to cite or link to this publication:
author
, et al. (More)
(Less)
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Physical Chemistry C
volume
116
issue
51
pages
26898 - 26907
publisher
The American Chemical Society
external identifiers
  • wos:000312681500027
  • scopus:84871652984
ISSN
1932-7447
DOI
10.1021/jp3087804
language
English
LU publication?
yes
id
ab43ada1-64cd-4bd8-89b5-af23c5153e7a (old id 3504163)
date added to LUP
2013-02-21 13:43:18
date last changed
2017-08-06 03:16:05
@article{ab43ada1-64cd-4bd8-89b5-af23c5153e7a,
  abstract     = {We investigate the growth and the physical and optical properties of type-II heterostructured ZnTe/ZnSe colloidal nanocrystals, focusing on the role of the 7% lattice mismatch between the two materials in determining growth homogeneity and band structure. We find that the lattice mismatch between the two materials places limitations on the range of structures that can be grown, and for those in which coherent growth is achieved we present clear evidence that the low bulk modulus ZnTe cores are compressed by the higher modulus ZnSe shells, accentuating the red-shift of the excitonic state with increasing shell thickness. By employing a variety of characterization tools we build a clear picture of the core-shell architecture. We show how strain is manifested in structures with sharp core-shell interfaces and how intentional alloying of the interface can influence the growth and exciton energies. We show that a (2,6)-band effective mass model is able to distinguish between the as-grown "sharp" and "alloyed" interfaces, indicating that the alloyed structures incorporate reduced strain.},
  author       = {Fairclough, Simon M. and Tyrrell, Edward J. and Graham, Darren M. and Lunt, Patrick J. B. and Hardman, Samantha J. O. and Pietzsch, Annette and Hennies, Franz and Moghal, Jonathan and Flavell, Wendy R. and Watt, Andrew A. R. and Smith, Jason M.},
  issn         = {1932-7447},
  language     = {eng},
  number       = {51},
  pages        = {26898--26907},
  publisher    = {The American Chemical Society},
  series       = {Journal of Physical Chemistry C},
  title        = {Growth and Characterization of Strained and Alloyed Type-II ZnTe/ZnSe Core-Shell Nanocrystals},
  url          = {http://dx.doi.org/10.1021/jp3087804},
  volume       = {116},
  year         = {2012},
}