Publication Date:
2019
Description:
〈h3〉Abstract〈/h3〉
〈p〉We investigate the structural, magnetic, electronic, and mechanical properties of the full Heusler alloys (FHAs) Ti〈sub〉2〈/sub〉CoTl〈sub〉1−〈em〉x〈/em〉〈/sub〉Pb〈sub〉〈em〉x〈/em〉〈/sub〉 (〈em〉x〈/em〉 = 0.00, 0.25, 0.50, 0.75, 1.00) using first-principles calculations. The FHAs Ti〈sub〉2〈/sub〉CoTl〈sub〉1−〈em〉x〈/em〉〈/sub〉Pb〈sub〉〈em〉x〈/em〉〈/sub〉 have the half-metallic characters within lattice constant regions 5.799–6.707, 5.749–6.821, 5.749–6.982, 5.789–7.115, and 5.976–6.943 Å for 〈em〉x〈/em〉 = 0.00, 0.25, 0.50, 0.75, and 1.00, respectively. The negative formation energy, positive cohesion energy, and higher than room temperature Curie temperature indicate that the FHAs Ti〈sub〉2〈/sub〉CoTl〈sub〉1−〈em〉x〈/em〉〈/sub〉Pb〈sub〉〈em〉x〈/em〉〈/sub〉 are thermodynamically stable and can be used in spintronics and magnetoelectronics. The total magnetic moment per formula unit 〈span〉
〈span〉\(\mu_{\text{t}}\)〈/span〉
〈/span〉 of the FHAs Ti〈sub〉2〈/sub〉CoTl〈sub〉1−〈em〉x〈/em〉〈/sub〉Pb〈sub〉〈em〉x〈/em〉〈/sub〉 satisfies the Slater–Pauling rule 〈span〉
〈span〉\(\mu_{\text{t}} = Z{}_{\text{t}} - 18\)〈/span〉
〈/span〉, where 〈span〉
〈span〉\(Z_{\text{t}}\)〈/span〉
〈/span〉 represents the total number of valence electrons per formula unit. With increasing Pb atom concentration 〈em〉x〈/em〉, the band structures in both spin-up and spin-down channels move toward low energy region, but the spin-down indirect band gap 〈span〉
〈span〉\(E_{g}^{ \downarrow }\)〈/span〉
〈/span〉 increases. In addition, the calculated elastic constants and elastic modulus indicate that the FHAs Ti〈sub〉2〈/sub〉CoTl〈sub〉1−〈em〉x〈/em〉〈/sub〉Pb〈sub〉〈em〉x〈/em〉〈/sub〉 have mechanical stability, as well as ductility and strong resistance to fracture and plastic deformation.〈/p〉
Print ISSN:
0947-8396
Electronic ISSN:
1432-0630
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
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