The Experts below are selected from a list of 19758 Experts worldwide ranked by ideXlab platform
Yasuhiko Arakawa - One of the best experts on this subject based on the ideXlab platform.
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effects of Accumulated Strain on the surface and optical properties of stacked 1 3 μm inas gaas quantum dot structures
Physica E-low-dimensional Systems & Nanostructures, 2008Co-Authors: Tao Yang, Jun Tatebayashi, Masao Nishioka, Yasuhiko ArakawaAbstract:We report the effects of Accumulated Strain by stacking on the surface and optical properties of stacked 1.3 mu m InAs/GaAs quantum dot (QD) structures grown by MOCVD. It is found that the surface of the stacked QD structures becomes more and more undulated with stacking, due to the increased Strain in the stacked QD structures with stacking. The photoluminescence intensity from the QD structures first increases as the stacking number increases from 1 to 3 and then dramatically decreases as it further increases, implying a significant increase in the density of crystal defects in the stacked QD structures due to the Accumulated Strain. Furthermore, we demonstrate that the Strain can be reduced by simply introducing annealing steps just after growing the GaAs spacers during the deposition of the stacked QD structures, leading to significant improvement in the surface and optical properties of the structures. (C) 2007 Elsevier B.V. All rights reserved.
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Effects of Accumulated Strain on the surface and optical properties of stacked 1.3 μm InAs/GaAs quantum dot structures
Physica E: Low-dimensional Systems and Nanostructures, 2008Co-Authors: Tao Yang, Jun Tatebayashi, Masao Nishioka, Yasuhiko ArakawaAbstract:We report the effects of Accumulated Strain by stacking on the surface and optical properties of stacked 1.3 mu m InAs/GaAs quantum dot (QD) structures grown by MOCVD. It is found that the surface of the stacked QD structures becomes more and more undulated with stacking, due to the increased Strain in the stacked QD structures with stacking. The photoluminescence intensity from the QD structures first increases as the stacking number increases from 1 to 3 and then dramatically decreases as it further increases, implying a significant increase in the density of crystal defects in the stacked QD structures due to the Accumulated Strain. Furthermore, we demonstrate that the Strain can be reduced by simply introducing annealing steps just after growing the GaAs spacers during the deposition of the stacked QD structures, leading to significant improvement in the surface and optical properties of the structures. (C) 2007 Elsevier B.V. All rights reserved.
A. L. Vorontsov - One of the best experts on this subject based on the ideXlab platform.
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Theoretical aspects of technological mechanics. 9. Strain and Accumulated Strain. Part 2
Russian Engineering Research, 2014Co-Authors: A. L. VorontsovAbstract:Attention focuses on determining the deformed state of a blank and taking account of the hardening in upsetting and during the insertion of a punch in a half-space.
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Theoretical aspects of technological mechanics. 9. Strain and Accumulated Strain. Part 1
Russian Engineering Research, 2014Co-Authors: A. L. VorontsovAbstract:Attention focuses on determining the deformed state of a blank and taking account of the hardening by means of applied plasticity theory. New solutions are outlined for the deformed state of the blank in upsetting and during the insertion of a punch in a half-space.
Tao Yang - One of the best experts on this subject based on the ideXlab platform.
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effects of Accumulated Strain on the surface and optical properties of stacked 1 3 μm inas gaas quantum dot structures
Physica E-low-dimensional Systems & Nanostructures, 2008Co-Authors: Tao Yang, Jun Tatebayashi, Masao Nishioka, Yasuhiko ArakawaAbstract:We report the effects of Accumulated Strain by stacking on the surface and optical properties of stacked 1.3 mu m InAs/GaAs quantum dot (QD) structures grown by MOCVD. It is found that the surface of the stacked QD structures becomes more and more undulated with stacking, due to the increased Strain in the stacked QD structures with stacking. The photoluminescence intensity from the QD structures first increases as the stacking number increases from 1 to 3 and then dramatically decreases as it further increases, implying a significant increase in the density of crystal defects in the stacked QD structures due to the Accumulated Strain. Furthermore, we demonstrate that the Strain can be reduced by simply introducing annealing steps just after growing the GaAs spacers during the deposition of the stacked QD structures, leading to significant improvement in the surface and optical properties of the structures. (C) 2007 Elsevier B.V. All rights reserved.
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Effects of Accumulated Strain on the surface and optical properties of stacked 1.3 μm InAs/GaAs quantum dot structures
Physica E: Low-dimensional Systems and Nanostructures, 2008Co-Authors: Tao Yang, Jun Tatebayashi, Masao Nishioka, Yasuhiko ArakawaAbstract:We report the effects of Accumulated Strain by stacking on the surface and optical properties of stacked 1.3 mu m InAs/GaAs quantum dot (QD) structures grown by MOCVD. It is found that the surface of the stacked QD structures becomes more and more undulated with stacking, due to the increased Strain in the stacked QD structures with stacking. The photoluminescence intensity from the QD structures first increases as the stacking number increases from 1 to 3 and then dramatically decreases as it further increases, implying a significant increase in the density of crystal defects in the stacked QD structures due to the Accumulated Strain. Furthermore, we demonstrate that the Strain can be reduced by simply introducing annealing steps just after growing the GaAs spacers during the deposition of the stacked QD structures, leading to significant improvement in the surface and optical properties of the structures. (C) 2007 Elsevier B.V. All rights reserved.
R Srinivasan - One of the best experts on this subject based on the ideXlab platform.
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a comparison of the properties of spd processed aa 6061 by equal channel angular pressing multi axial compressions forgings and accumulative roll bonding
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2005Co-Authors: Balakrishna Cherukuri, Teodora S Nedkova, R SrinivasanAbstract:Abstract Commercially available AA-6061 in the annealed condition was subject to severe plastic deformation (SPD) processing by equal-channel angular pressing (ECAP), multi-axial compression/forgings (MAC/F) and accumulative roll bonding (ARB) at room temperature to approximately the same Accumulated Strain (∼4). Micro-hardness testing showed that materials processed by ECAP, MAC/F and ARB followed the same trend. The tensile properties of MAC/F- and ARB-processed materials were compared with those of the ECAP-processed material from the literature. MAC/F material exhibited high Strain rate sensitivity in the temperature range of 300–350 °C. The SPD technique used, whether ECAP, MAC/F or ARB, did not significantly affect the flow behavior of AA-6061.
P F Thomso - One of the best experts on this subject based on the ideXlab platform.
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the effect of through thickness Strain distribution on the static recrystallization of hot rolled austenitic stainless steel strip
Journal of Materials Processing Technology, 1996Co-Authors: X J Zhang, Pete Hodgso, P F ThomsoAbstract:Abstract The accumulation of Strain and the evolution of the microstructures at the surface and centre of thin hot rolled 304 austenitic stainless steel strips were studied by comparing their recrystallisation behaviour and recrystallised grain sizes. It appears that the evolution of microstructure can be predicated using a simple approach and that the Accumulated Strain depends only on the amount of Strain, and not on the Strain path (ie. the effect of Strain reversal in the roll gap.) This was confirmed by the observation that the time for 50% recrystallisation and the recrystallised grain size were found to be approximately a log linear function of Strain when the Strain in the centre of the hot rolled strips was calculated from the rolling reduction and the Strain in the surface region was estimated from the predicted ratio of surface Strain to axial Strain obtained from FE modelling using the commercial package ABAQUS.
