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Md. Riad Kasem

Other affiliations: University of Dhaka
Bio: Md. Riad Kasem is an academic researcher from Tokyo Metropolitan University. The author has contributed to research in topics: Superconductivity & Physics. The author has an hindex of 4, co-authored 13 publications receiving 51 citations. Previous affiliations of Md. Riad Kasem include University of Dhaka.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the authors explored new high-entropy-alloy (HEA) superconductors and discovered a CuAl2-type superconductor Co0.2.
Abstract: Research on high-entropy-alloy (HEA) superconductors is a growing field in material science. In this study, we explored new HEA-type superconductors and discovered a CuAl2-type superconductor Co0.2...

30 citations

Journal ArticleDOI
TL;DR: In this article, the synthesis and superconductivity of high-entropy-alloy-type (HEA-type) compounds TrZr2 (Tr = Fe, Co, Ni, Rh, Ir), in which the Tr site satisfies the criterion of HEA, were reported.
Abstract: We report on the synthesis and superconductivity of high-entropy-alloy-type (HEA-type) compounds TrZr2 (Tr = Fe, Co, Ni, Rh, Ir), in which the Tr site satisfies the criterion of HEA. Polycrystalline samples of HEA-type TrZr2 with four different compositions at the Tr site were synthesized by arc melting method. The phase purity and crystal structure were examined by Rietveld refinement of X-ray diffraction profile. It has been confirmed that the obtained samples have a CuAl2-type tetragonal structure. From analyses of elemental composition and mixing entropy at the Tr site, the HEA state for the Tr site was confirmed. The physical properties of obtained samples were characterized by electrical resistivity and magnetization measurements. All the samples show bulk superconductivity with various transition temperature (Tc). The Tc varied according to the compositions and showed correlations with the lattice constant c and Tr-Zr bond lengths. Introduction of an HEA site in TrZr2 is useful to achieve systematic tuning of Tc with a wide temperature range, which would be a merit for superconductivity application.

22 citations

Journal ArticleDOI
TL;DR: In this article, a superconducting transition was observed at 8.0 K after electrical resistivity, magnetization, and specific heat measurements, and the bulk characteristics of the superconductivity were confirmed through the specific heat measurement.
Abstract: Research on high-entropy-alloy (HEA) superconductors is a growing field in material science. In this study, we explored new HEA-type superconductors and discovered a CuAl2-type superconductor Co0.2Ni0.1Cu0.1Rh0.3Ir0.3Zr2 with a HEA-type transition metal site. A superconducting transition was observed at 8.0 K after electrical resistivity, magnetization, and specific heat measurements. The bulk characteristics of the superconductivity were confirmed through the specific heat measurements. The discovery of superconductivity in HEA-type Co0.2Ni0.1Cu0.1Rh0.3Ir0.3Zr2 will provide a novel pathway to explore new HEA-type superconductors and investigate the relationship between the mixing entropy and superconductivity of HEA-type compounds.

18 citations

Journal ArticleDOI
TL;DR: In this article, high-entropy-alloy-type tellurides M-Te, which contain five different metals of M = Ag, In, Cd, Sn, Sb, Pb, and Bi, were synthesized using high pressure synthesis.
Abstract: High-entropy-alloy-type tellurides M-Te, which contain five different metals of M = Ag, In, Cd, Sn, Sb, Pb, and Bi, were synthesized using high pressure synthesis. Structural characterization revealed that all the obtained samples have a cubic NaCl-type structure. Six samples, namely AgCdSnSbPbTe5, AgInSnSbPbTe5, AgCdInSnSbTe5, AgCdSnPbBiTe5, AgCdInPbBiTe5, and AgCdInSnBiTe5 showed superconductivity. The highest transition temperature (T c) among those samples was 1.4 K for AgInSnSbPbTe5. A sample of AgCdInSbPbTe5 showed a semiconductor-like transport behavior. From the relationship between T c and lattice constant, it was found that a higher T c is observed for a telluride with a larger lattice constant.

17 citations

Journal ArticleDOI
TL;DR: In this article, high-entropy-alloy-type tellurides M-Te, which contain five different metals of M = Ag, In, Cd, Sn, Sb, Pb, and Bi, were synthesized using high pressure synthesis.
Abstract: High-entropy-alloy-type tellurides M-Te, which contain five different metals of M = Ag, In, Cd, Sn, Sb, Pb, and Bi, were synthesized using high pressure synthesis. Structural characterization revealed that all the obtained samples have a cubic NaCl-type structure. Six samples, namely AgCdSnSbPbTe5, AgInSnSbPbTe5, AgCdInSnSbTe5, AgCdSnPbBiTe5, AgCdInPbBiTe5, and AgCdInSnBiTe5 showed superconductivity. The highest transition temperature (Tc) among those samples was 1.4 K for AgInSnSbPbTe5. A sample of AgCdInSbPbTe5 showed a semiconductor-like transport behavior. From the relationship between Tc and lattice constant, it was found that a higher Tc is observed for a telluride with a larger lattice constant.

13 citations


Cited by
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Dissertation
01 Oct 1948
TL;DR: In this article, it was shown that a metal should be superconductive if a set of corners of a Brillouin zone is lying very near the Fermi surface, considered as a sphere, which limits the region in the momentum space completely filled with electrons.
Abstract: IN two previous notes1, Prof. Max Born and I have shown that one can obtain a theory of superconductivity by taking account of the fact that the interaction of the electrons with the ionic lattice is appreciable only near the boundaries of Brillouin zones, and particularly strong near the corners of these. This leads to the criterion that the metal should be superconductive if a set of corners of a Brillouin zone is lying very near the Fermi surface, considered as a sphere, which limits the region in the momentum space completely filled with electrons.

2,042 citations

Journal ArticleDOI
10 Aug 2020
TL;DR: In this article, a review of the research status of high-entropy alloys (HEAs) superconductors is presented, where the concept of HEA is extended to materials possessing multiple crystallographic sites; thus, the authors also introduce multisite HEAs with the CsCl-type, α-Mn type, A15, NaCl type, σ-phase and layered structures.
Abstract: High-entropy alloys (HEAs) are a new class of materials which are being energetically studied around the world. HEAs are characterized by a multicomponent alloy in which five or more elements randomly occupy a crystallographic site. The conventional HEA concept has developed into simple crystal structures such as face-centered-cubic (fcc), body-centered-cubic (bcc) and hexagonal-closed packing (hcp) structures. The highly atomic-disordered state produces many superior mechanical or thermal properties. Superconductivity has been one of the topics of focus in the field of HEAs since the discovery of the bcc HEA superconductor in 2014. A characteristic of superconductivity is robustness against atomic disorder or extremely high pressure. The materials research on HEA superconductors has just begun, and there are open possibilities for unexpectedly finding new phenomena. The present review updates the research status of HEA superconductors. We survey bcc and hcp HEA superconductors and discuss the simple material design. The concept of HEA is extended to materials possessing multiple crystallographic sites; thus, we also introduce multisite HEA superconductors with the CsCl-type, α-Mn-type, A15, NaCl-type, σ-phase and layered structures and discuss the materials research on multisite HEA superconductors. Finally, we present the new perspectives of eutectic HEA superconductors and gum metal HEA superconductors.

47 citations

Journal ArticleDOI
05 Nov 2021-Small
TL;DR: In this paper, the latest advances in HEA electrocatalysts are systematically summarized, with special focus on nitrogen fixation, the carbon cycle, water splitting, and fuel cells; in addition, by combining this with the characterization and analysis of HEA microstructures, rational design strategies for optimizing HEAs, including controllable preparation, component regulation, strain engineering, defect engineering, and theoretical prediction are proposed.
Abstract: High-entropy alloys (HEAs) are expected to function well as electrocatalytic materials, owing to their widely adjustable composition and unique physical and chemical properties. Recently, HEA catalysts are extensively studied in the field of electrocatalysis; this motivated the authors to investigate the relationship between the structure and composition of HEAs and their electrocatalytic performance. In this review, the latest advances in HEA electrocatalysts are systematically summarized, with special focus on nitrogen fixation, the carbon cycle, water splitting, and fuel cells; in addition, by combining this with the characterization and analysis of HEA microstructures, rational design strategies for optimizing HEA electrocatalysts, including controllable preparation, component regulation, strain engineering, defect engineering, and theoretical prediction are proposed. Moreover, the existing issues and future trends of HEAs are predicted, which will help further develop these high-entropy materials.

39 citations

Journal ArticleDOI
TL;DR: The synthesis and observation of polycrystalline samples of new high-entropy-alloy-type metal chalcogenides (Ag,In,Pb,Bi)Te1-xSex with NaCl-type structure are reported, which show the multi-site alloying effect on the entropy of mixing ( ΔSmix) for the examined samples.
Abstract: We propose an efficient way of increasing the entropy of mixing in high-entropy-alloy-type compounds, which can be achieved by multi-site alloying. As an example of this concept, we report the synthesis and observation of polycrystalline samples of new high-entropy-alloy-type metal chalcogenides (Ag,In,Pb,Bi)Te1-xSex (x = 0.0, 0.25, and 0.5) with a NaCl-type structure. The samples were synthesized using high pressure synthesis. Superconductivity with transition temperatures of 2.7, 2.5, and 2.0 K was observed with x = 0.0, 0.25, and 0.5, respectively. To investigate the multi-site alloying effect on the entropy of mixing (ΔSmix) for the examined samples, we calculated the total ΔSmix for two crystallographic sites. For the samples with x = 0.25 and 0.5, ΔSmix reaches 1.89R and 2.00R, respectively, which exceed the ΔSmix of 1.79R for a simple (single-site) high-entropy alloy containing six different elements.

32 citations

Journal ArticleDOI
TL;DR: In this paper, the authors explored new high-entropy-alloy (HEA) superconductors and discovered a CuAl2-type superconductor Co0.2.
Abstract: Research on high-entropy-alloy (HEA) superconductors is a growing field in material science. In this study, we explored new HEA-type superconductors and discovered a CuAl2-type superconductor Co0.2...

30 citations