Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Formation of two-dimensionally confined superparamagnetic (Mn, Ga)As nanocrystals in high-temperature annealed (Ga, Mn)As/GaAs superlattices

Sadowski, Janusz LU ; Jaroslaw Z, Domagala ; Roland, Mathieu ; Andras, Kovacs and Piotr, Dluzewski (2013) In Journal of Physics: Condensed Matter 25(19). p.6-196005
Abstract
The annealing-induced formation of (Mn, Ga)As nanocrystals in (Ga, Mn)As/GaAs superlattices was studied by x-ray diffraction, transmission electron microscopy and magnetometry. The superlattice structures with 50 Å thick (Ga, Mn)As layers separated by 25, 50 and 100 Å thick GaAs spacers were grown by molecular beam epitaxy at low temperature (250 ° C), and then annealed at high temperatures of 400, 560 and 630 ° C. The high-temperature annealing causes decomposition to a (Ga, Mn)As ternary alloy and the formation of (Mn, Ga)As nanocrystals inside the GaAs matrix. The nanocrystals are confined in the planes that were formerly occupied by (Ga, Mn)As layers for the up to 560 ° C annealing and diffuse throughout the GaAs spacer layers at 630 °... (More)
The annealing-induced formation of (Mn, Ga)As nanocrystals in (Ga, Mn)As/GaAs superlattices was studied by x-ray diffraction, transmission electron microscopy and magnetometry. The superlattice structures with 50 Å thick (Ga, Mn)As layers separated by 25, 50 and 100 Å thick GaAs spacers were grown by molecular beam epitaxy at low temperature (250 ° C), and then annealed at high temperatures of 400, 560 and 630 ° C. The high-temperature annealing causes decomposition to a (Ga, Mn)As ternary alloy and the formation of (Mn, Ga)As nanocrystals inside the GaAs matrix. The nanocrystals are confined in the planes that were formerly occupied by (Ga, Mn)As layers for the up to 560 ° C annealing and diffuse throughout the GaAs spacer layers at 630 ° C annealing. The two-dimensionally confined nanocrystals exhibit a superparamagnetic behavior which becomes high-temperature ferromagnetism (~350 K) upon diffusion. (Less)
Please use this url to cite or link to this publication:
author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
ferromagnetic semiconductors, magnetic nanocrystals, Molecular Beam Epitaxy
in
Journal of Physics: Condensed Matter
volume
25
issue
19
pages
6 - 196005
publisher
IOP Publishing
external identifiers
  • wos:000318070100027
  • scopus:84876938151
ISSN
1361-648X
DOI
10.1088/0953-8984/25/19/196005
language
English
LU publication?
yes
id
5119c3ef-89ff-4a90-bbb2-77bb0e380940 (old id 3635954)
date added to LUP
2016-04-01 13:40:30
date last changed
2022-03-31 14:53:43
@article{5119c3ef-89ff-4a90-bbb2-77bb0e380940,
  abstract     = {{The annealing-induced formation of (Mn, Ga)As nanocrystals in (Ga, Mn)As/GaAs superlattices was studied by x-ray diffraction, transmission electron microscopy and magnetometry. The superlattice structures with 50 Å thick (Ga, Mn)As layers separated by 25, 50 and 100 Å thick GaAs spacers were grown by molecular beam epitaxy at low temperature (250 ° C), and then annealed at high temperatures of 400, 560 and 630 ° C. The high-temperature annealing causes decomposition to a (Ga, Mn)As ternary alloy and the formation of (Mn, Ga)As nanocrystals inside the GaAs matrix. The nanocrystals are confined in the planes that were formerly occupied by (Ga, Mn)As layers for the up to 560 ° C annealing and diffuse throughout the GaAs spacer layers at 630 ° C annealing. The two-dimensionally confined nanocrystals exhibit a superparamagnetic behavior which becomes high-temperature ferromagnetism (~350 K) upon diffusion.}},
  author       = {{Sadowski, Janusz and Jaroslaw Z, Domagala and Roland, Mathieu and Andras, Kovacs and Piotr, Dluzewski}},
  issn         = {{1361-648X}},
  keywords     = {{ferromagnetic semiconductors; magnetic nanocrystals; Molecular Beam Epitaxy}},
  language     = {{eng}},
  number       = {{19}},
  pages        = {{6--196005}},
  publisher    = {{IOP Publishing}},
  series       = {{Journal of Physics: Condensed Matter}},
  title        = {{Formation of two-dimensionally confined superparamagnetic (Mn, Ga)As nanocrystals in high-temperature annealed (Ga, Mn)As/GaAs superlattices}},
  url          = {{http://dx.doi.org/10.1088/0953-8984/25/19/196005}},
  doi          = {{10.1088/0953-8984/25/19/196005}},
  volume       = {{25}},
  year         = {{2013}},
}