The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Yoshiyuki Kawazoe - One of the best experts on this subject based on the ideXlab platform.
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vacancy induced structural and Magnetic Transition in mnco1 xge
Applied Physics Letters, 2006Co-Authors: Jian-tao Wang, Ding-sheng Wang, O. Nashima, T Kanomata, Changfeng Chen, Hiroshi Mizuseki, Yoshiyuki KawazoeAbstract:The authors report ab initio total energy calculations on the first-order structural Transition of the ferroMagnetic MnCo1−xGe(0.00⩽x⩽0.25) intermetallic compound. They show that increasing Co vacancies induce a Transition from an orthorhombic structure at 0⩽x⩽0.08 to a hexagonal structure at x>0.08. A concomitant high-to-low moment Magnetic Transition and a large magnetovolume effect occur due to the change of the symmetry and the resulting coupling distance between the Magnetic atoms. These results provide an excellent account for the experimental results and reveal the crucial role of the Co vacancies in determining the relative structural stability and the Magnetic properties of MnCo1−xGe.
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Vacancy induced structural and Magnetic Transition in MnCo1−xGe
Applied Physics Letters, 2006Co-Authors: Jian-tao Wang, Ding-sheng Wang, O. Nashima, T Kanomata, Changfeng Chen, Hiroshi Mizuseki, Yoshiyuki KawazoeAbstract:The authors report ab initio total energy calculations on the first-order structural Transition of the ferroMagnetic MnCo1−xGe(0.00⩽x⩽0.25) intermetallic compound. They show that increasing Co vacancies induce a Transition from an orthorhombic structure at 0⩽x⩽0.08 to a hexagonal structure at x>0.08. A concomitant high-to-low moment Magnetic Transition and a large magnetovolume effect occur due to the change of the symmetry and the resulting coupling distance between the Magnetic atoms. These results provide an excellent account for the experimental results and reveal the crucial role of the Co vacancies in determining the relative structural stability and the Magnetic properties of MnCo1−xGe.
Wenyu Zhao - One of the best experts on this subject based on the ideXlab platform.
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Magnetoelectric interaction and transport behaviours in Magnetic nanocomposite thermoelectric materials
Nature Nanotechnology, 2017Co-Authors: Wenyu Zhao, Wanting Zhu, Zhiyuan Liu, Xianli Su, Xinfeng Tang, Jihui Yang, Yong Liu, Qingjie Zhang, Ping Wei, Jing ShiAbstract:How to suppress the performance deterioration of thermoelectric materials in the intrinsic excitation region remains a key challenge. The Magnetic Transition of permanent magnet nanoparticles from ferromagnetism to paramagnetism provides an effective approach to finding the solution to this challenge. Here, we have designed and prepared Magnetic nanocomposite thermoelectric materials consisting of BaFe12O19 nanoparticles and Ba0.3In0.3Co4Sb12 matrix. It was found that the electrical transport behaviours of the nanocomposites are controlled by the Magnetic Transition of BaFe12O19 nanoparticles from ferromagnetism to paramagnetism. BaFe12O19 nanoparticles trap electrons below the Curie temperature (TC) and release the trapped electrons above the TC, playing an ‘electron repository’ role in maintaining high figure of merit ZT. BaFe12O19 nanoparticles produce two types of magnetoelectric effect—electron spiral motion and magnon-drag thermopower—as well as enhancing phonon scattering. Our work demonstrates that the performance deterioration of thermoelectric materials in the intrinsic excitation region can be suppressed through the Magnetic Transition of permanent magnet nanoparticles.
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magnetoelectric interaction and transport behaviours in Magnetic nanocomposite thermoelectric materials
Nature Nanotechnology, 2017Co-Authors: Wenyu Zhao, Xianli Su, Xinfeng Tang, Jihui Yang, Qingjie Zhang, Yimin ChaoAbstract:How to suppress the performance deterioration of thermoelectric materials in the intrinsic excitation region remains a key challenge. The Magnetic Transition of permanent magnet nanoparticles from ferromagnetism to paramagnetism provides an effective approach to finding the solution to this challenge. Here, we have designed and prepared Magnetic nanocomposite thermoelectric materials consisting of BaFe12O19 nanoparticles and Ba0.3In0.3Co4Sb12 matrix. It was found that the electrical transport behaviours of the nanocomposites are controlled by the Magnetic Transition of BaFe12O19 nanoparticles from ferromagnetism to paramagnetism. BaFe12O19 nanoparticles trap electrons below the Curie temperature (TC) and release the trapped electrons above the TC, playing an ‘electron repository’ role in maintaining high figure of merit ZT. BaFe12O19 nanoparticles produce two types of magnetoelectric effect—electron spiral motion and magnon-drag thermopower—as well as enhancing phonon scattering. Our work demonstrates that the performance deterioration of thermoelectric materials in the intrinsic excitation region can be suppressed through the Magnetic Transition of permanent magnet nanoparticles. The ferroMagnetic Transition in Magnetic nanoparticles embedded in Magnetic nanocomposite thermoelectric materials is attributed to the trapping and release of electrons, which increases the performance of the thermoelectric materials.
G. Chandra - One of the best experts on this subject based on the ideXlab platform.
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Electrical resistivity, thermopower and thermal conductivity studies in RNiGe (RGd, Tb, Dy, Er, Ho, Y) systems
Journal of Alloys and Compounds, 1993Co-Authors: C. S. Garde, J. Ray, G. ChandraAbstract:We report here transport studies on the rare earth equiatomic germanide RNiGe systems between 4.2 and 300 K. Some of the systems (R Gd, Tb, Dy) show evidence of Magnetic Transition from our electrical resistivity ρ{variant} studies. For R Tb, two clear Transitions at temperatures of 18 K and 9 K have been observed in contrast to a single Transition, at 7 K, from the earlier Magnetic study. In the case of R Er, no Magnetic Transition has been observed down to 4.2 K from our ρ{variant} studies, whereas the previous Magnetic study revealed the presence of a Magnetic Transition at around 6 K. In addition, both the thermopower S and the thermal conductivity λ data exhibit complex behaviour at low temperatures. © 1993.
Yimin Chao - One of the best experts on this subject based on the ideXlab platform.
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magnetoelectric interaction and transport behaviours in Magnetic nanocomposite thermoelectric materials
Nature Nanotechnology, 2017Co-Authors: Wenyu Zhao, Xianli Su, Xinfeng Tang, Jihui Yang, Qingjie Zhang, Yimin ChaoAbstract:How to suppress the performance deterioration of thermoelectric materials in the intrinsic excitation region remains a key challenge. The Magnetic Transition of permanent magnet nanoparticles from ferromagnetism to paramagnetism provides an effective approach to finding the solution to this challenge. Here, we have designed and prepared Magnetic nanocomposite thermoelectric materials consisting of BaFe12O19 nanoparticles and Ba0.3In0.3Co4Sb12 matrix. It was found that the electrical transport behaviours of the nanocomposites are controlled by the Magnetic Transition of BaFe12O19 nanoparticles from ferromagnetism to paramagnetism. BaFe12O19 nanoparticles trap electrons below the Curie temperature (TC) and release the trapped electrons above the TC, playing an ‘electron repository’ role in maintaining high figure of merit ZT. BaFe12O19 nanoparticles produce two types of magnetoelectric effect—electron spiral motion and magnon-drag thermopower—as well as enhancing phonon scattering. Our work demonstrates that the performance deterioration of thermoelectric materials in the intrinsic excitation region can be suppressed through the Magnetic Transition of permanent magnet nanoparticles. The ferroMagnetic Transition in Magnetic nanoparticles embedded in Magnetic nanocomposite thermoelectric materials is attributed to the trapping and release of electrons, which increases the performance of the thermoelectric materials.
Jian-tao Wang - One of the best experts on this subject based on the ideXlab platform.
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vacancy induced structural and Magnetic Transition in mnco1 xge
Applied Physics Letters, 2006Co-Authors: Jian-tao Wang, Ding-sheng Wang, O. Nashima, T Kanomata, Changfeng Chen, Hiroshi Mizuseki, Yoshiyuki KawazoeAbstract:The authors report ab initio total energy calculations on the first-order structural Transition of the ferroMagnetic MnCo1−xGe(0.00⩽x⩽0.25) intermetallic compound. They show that increasing Co vacancies induce a Transition from an orthorhombic structure at 0⩽x⩽0.08 to a hexagonal structure at x>0.08. A concomitant high-to-low moment Magnetic Transition and a large magnetovolume effect occur due to the change of the symmetry and the resulting coupling distance between the Magnetic atoms. These results provide an excellent account for the experimental results and reveal the crucial role of the Co vacancies in determining the relative structural stability and the Magnetic properties of MnCo1−xGe.
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Vacancy induced structural and Magnetic Transition in MnCo1−xGe
Applied Physics Letters, 2006Co-Authors: Jian-tao Wang, Ding-sheng Wang, O. Nashima, T Kanomata, Changfeng Chen, Hiroshi Mizuseki, Yoshiyuki KawazoeAbstract:The authors report ab initio total energy calculations on the first-order structural Transition of the ferroMagnetic MnCo1−xGe(0.00⩽x⩽0.25) intermetallic compound. They show that increasing Co vacancies induce a Transition from an orthorhombic structure at 0⩽x⩽0.08 to a hexagonal structure at x>0.08. A concomitant high-to-low moment Magnetic Transition and a large magnetovolume effect occur due to the change of the symmetry and the resulting coupling distance between the Magnetic atoms. These results provide an excellent account for the experimental results and reveal the crucial role of the Co vacancies in determining the relative structural stability and the Magnetic properties of MnCo1−xGe.
