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Abstract We report a theoretical investigation of effects of Mn and Co substitution in the transition metal sites of the kagomé-lattice ferromagnet, Fe3Sn2. Herein, hole- and electron-doping effects of Fe3Sn2have been studied by density-functional theory calculations on the parent phase and on the substituted structural models of Fe3−xMxSn2(M = Mn, Co;x= 0.5, 1.0). All optimized structures favor the ferromagnetic ground state. Analysis of the electronic density of states (DOS) and band structure plots reveals that the hole (electron) doping leads to a progressive decrease (increase) in the magnetic moment per Fe atom and per unit cell overall. The high DOS is retained nearby the Fermi level in the case of both Mn and Co substitutions. The electron doping with Co results in the loss of nodal band degeneracies, while in the case of hole doping with Mn emergent nodal band degeneracies and flatbands initially are suppressed in Fe2.5Mn0.5Sn2but re-emerge in Fe2MnSn2. These results provide key insights into potential modifications of intriguing coupling between electronic and spin degrees of freedom observed in Fe3Sn2.
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Predictive study of Mn- and Co-based van der Waals compounds for spintronic and quantum applications
Abstract This study investigates the structural, electronic, and magnetic properties of XBr2, XI2, and XBrI (X = Mn, Co) compounds using density functional theory, incorporating spin–orbit coupling and the GGA + U framework. Cohesive and formation energy calculations reveal that MnBr2is most stable in the ferromagnetic phase, while the other compounds favor antiferromagnetic ordering. The inclusion of the effective Coulomb screening potential (Ueff) enhances the localization of 3d orbitals, leading to increased magnetic moments. Electronic structure analyses show that most compounds transition to semiconducting behavior in the antiferromagnetic phase—except CoI2—while MnBr2, CoBr2, and CoI2exhibit half-metallicity in the ferrimagnetic phase. In the antiferromagnetic phase, MnBr2, MnI2, and MnBrI display topological Dirac-like points between theRand Γ points, suggesting the presence of massless fermions and enabling phenomena such as the quantum Hall effect and ultra-high carrier mobility. The computational results are consistent with available experimental data, highlighting the potential of Mn- and Co-based van der Waals compounds for spintronic and quantum applications.
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- Award ID(s):
- 2110603
- PAR ID:
- 10593265
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Materials Science
- Volume:
- 60
- Issue:
- 21
- ISSN:
- 0022-2461
- Format(s):
- Medium: X Size: p. 8749-8765
- Size(s):
- p. 8749-8765
- Sponsoring Org:
- National Science Foundation
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