MnAs dots grown on GaN( 000(1)over-bar)-(1x1) surface
(2007) In Physical Review B (Condensed Matter and Materials Physics) 75(23).- Abstract
- MnAs has been grown by means of MBE on the GaN(000 (1) over bar)-(1x1) surface. Two options of initiating the crystal growth were applied: (a) a regular MBE procedure (manganese and arsenic were delivered simultaneously) and (b) subsequent deposition of manganese and arsenic layers. It was shown that spontaneous formation of MnAs dots with the surface density of 1x10(11) cm(-2) and 2.5x10(11) cm(-2), respectively (as observed by atomic force microscopy), occurred for the layer thickness higher than 5 ML. Electronic structure of the MnAs/GaN systems was studied by resonant photoemission spectroscopy. That led to determination of the Mn 3d-related contribution to the total density of states distribution of MnAs. It has been proven that the... (More)
- MnAs has been grown by means of MBE on the GaN(000 (1) over bar)-(1x1) surface. Two options of initiating the crystal growth were applied: (a) a regular MBE procedure (manganese and arsenic were delivered simultaneously) and (b) subsequent deposition of manganese and arsenic layers. It was shown that spontaneous formation of MnAs dots with the surface density of 1x10(11) cm(-2) and 2.5x10(11) cm(-2), respectively (as observed by atomic force microscopy), occurred for the layer thickness higher than 5 ML. Electronic structure of the MnAs/GaN systems was studied by resonant photoemission spectroscopy. That led to determination of the Mn 3d-related contribution to the total density of states distribution of MnAs. It has been proven that the electronic structures of the MnAs dots grown by the two procedures differ markedly. One corresponds to metallic, ferromagnetic NiAs-type MnAs, the other is similar to that reported for half-metallic zinc-blende MnAs. Both systems behave superparamagnetically (as revealed by magnetization measurements), but with both the blocking temperatures and the intradot Curie temperatures substantially different. The intradot Curie temperature is about 260 K for the former system while markedly higher than room temperature for the latter one. Relations between growth process, electronic structure, and other properties of the studied systems are discussed. Possible mechanisms of half-metallic MnAs formation on GaN are considered. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/646208
- author
- Kowalik, I. A. ; Kowalski, B. J. ; Iwanowski, R. J. ; Kopalko, K. ; Lusakowska, E. ; Sawicki, M. ; Sadowski, Janusz LU ; Adell, M. ; Grzegory, I. and Porowski, S.
- organization
- publishing date
- 2007
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review B (Condensed Matter and Materials Physics)
- volume
- 75
- issue
- 23
- publisher
- American Physical Society
- external identifiers
-
- wos:000247624900075
- scopus:34347391704
- ISSN
- 1098-0121
- DOI
- 10.1103/PhysRevB.75.235303
- language
- English
- LU publication?
- yes
- id
- 01725322-dd3a-4f0a-8a83-e0603e90b0c8 (old id 646208)
- date added to LUP
- 2016-04-01 16:29:34
- date last changed
- 2022-03-31 14:50:57
@article{01725322-dd3a-4f0a-8a83-e0603e90b0c8, abstract = {{MnAs has been grown by means of MBE on the GaN(000 (1) over bar)-(1x1) surface. Two options of initiating the crystal growth were applied: (a) a regular MBE procedure (manganese and arsenic were delivered simultaneously) and (b) subsequent deposition of manganese and arsenic layers. It was shown that spontaneous formation of MnAs dots with the surface density of 1x10(11) cm(-2) and 2.5x10(11) cm(-2), respectively (as observed by atomic force microscopy), occurred for the layer thickness higher than 5 ML. Electronic structure of the MnAs/GaN systems was studied by resonant photoemission spectroscopy. That led to determination of the Mn 3d-related contribution to the total density of states distribution of MnAs. It has been proven that the electronic structures of the MnAs dots grown by the two procedures differ markedly. One corresponds to metallic, ferromagnetic NiAs-type MnAs, the other is similar to that reported for half-metallic zinc-blende MnAs. Both systems behave superparamagnetically (as revealed by magnetization measurements), but with both the blocking temperatures and the intradot Curie temperatures substantially different. The intradot Curie temperature is about 260 K for the former system while markedly higher than room temperature for the latter one. Relations between growth process, electronic structure, and other properties of the studied systems are discussed. Possible mechanisms of half-metallic MnAs formation on GaN are considered.}}, author = {{Kowalik, I. A. and Kowalski, B. J. and Iwanowski, R. J. and Kopalko, K. and Lusakowska, E. and Sawicki, M. and Sadowski, Janusz and Adell, M. and Grzegory, I. and Porowski, S.}}, issn = {{1098-0121}}, language = {{eng}}, number = {{23}}, publisher = {{American Physical Society}}, series = {{Physical Review B (Condensed Matter and Materials Physics)}}, title = {{MnAs dots grown on GaN( 000(1)over-bar)-(1x1) surface}}, url = {{http://dx.doi.org/10.1103/PhysRevB.75.235303}}, doi = {{10.1103/PhysRevB.75.235303}}, volume = {{75}}, year = {{2007}}, }