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Title: Observation of atomic ordering of triple-period-A and -B type in GaAsBi

Abstract

We report the observation of atomic ordering of triple-period (TP)-A and -B type in low temperature (LT) grown GaAsBi alloy using transmission electron microscopy (TEM). In addition to previous reports, where only TP-A ordering was identified in III-V alloys, here, we confirm by electron diffraction, high-resolution (HR) TEM, and HR Z-contrast scanning TEM that two ordering variants coexists for LT-GaAsBi. We find that the TP-A ordering variant dominates over the TP-B variant. TP-A domains extend over 50–100 nm (projected lateral width) and are of higher perfection compared to TP-B domains. HR Z-contrast scanning TEM on different domains reveals a variation in the Bi occupancy in the (111) planes with triple period sequence. Since the formation of ordered phases has been directly linked to the occurrence of specific surface reconstructions, our results suggest a correlation between the TP-A and B type domains and the multiple stability of n × 3 and 3 × n reconstructions on the (001) surface of GaAsBi under low temperature growth.

Authors:
; ;  [1]; ;  [2]
  1. Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5–7, D-10117 Berlin (Germany)
  2. Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland)
Publication Date:
OSTI Identifier:
22311189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ARSENIC COMPOUNDS; BISMUTH COMPOUNDS; CORRELATIONS; CRYSTAL GROWTH; ELECTRON DIFFRACTION; GALLIUM COMPOUNDS; RESOLUTION; STABILITY; SURFACES; TERNARY ALLOY SYSTEMS; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Wu, Mingjian, E-mail: mingjian@pdi-berlin.de, Luna, Esperanza, Trampert, Achim, Puustinen, Janne, and Guina, Mircea. Observation of atomic ordering of triple-period-A and -B type in GaAsBi. United States: N. p., 2014. Web. doi:10.1063/1.4891854.
Wu, Mingjian, E-mail: mingjian@pdi-berlin.de, Luna, Esperanza, Trampert, Achim, Puustinen, Janne, & Guina, Mircea. Observation of atomic ordering of triple-period-A and -B type in GaAsBi. United States. doi:10.1063/1.4891854.
Wu, Mingjian, E-mail: mingjian@pdi-berlin.de, Luna, Esperanza, Trampert, Achim, Puustinen, Janne, and Guina, Mircea. Mon . "Observation of atomic ordering of triple-period-A and -B type in GaAsBi". United States. doi:10.1063/1.4891854.
@article{osti_22311189,
title = {Observation of atomic ordering of triple-period-A and -B type in GaAsBi},
author = {Wu, Mingjian, E-mail: mingjian@pdi-berlin.de and Luna, Esperanza and Trampert, Achim and Puustinen, Janne and Guina, Mircea},
abstractNote = {We report the observation of atomic ordering of triple-period (TP)-A and -B type in low temperature (LT) grown GaAsBi alloy using transmission electron microscopy (TEM). In addition to previous reports, where only TP-A ordering was identified in III-V alloys, here, we confirm by electron diffraction, high-resolution (HR) TEM, and HR Z-contrast scanning TEM that two ordering variants coexists for LT-GaAsBi. We find that the TP-A ordering variant dominates over the TP-B variant. TP-A domains extend over 50–100 nm (projected lateral width) and are of higher perfection compared to TP-B domains. HR Z-contrast scanning TEM on different domains reveals a variation in the Bi occupancy in the (111) planes with triple period sequence. Since the formation of ordered phases has been directly linked to the occurrence of specific surface reconstructions, our results suggest a correlation between the TP-A and B type domains and the multiple stability of n × 3 and 3 × n reconstructions on the (001) surface of GaAsBi under low temperature growth.},
doi = {10.1063/1.4891854},
journal = {Applied Physics Letters},
number = 4,
volume = 105,
place = {United States},
year = {Mon Jul 28 00:00:00 EDT 2014},
month = {Mon Jul 28 00:00:00 EDT 2014}
}
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