Doaa Ayad Kamil (1)
General Background: Two-dimensional magnetic materials are promising quantum systems for studying electronic structure, magnetic ordering, and thermal stability in low-dimensional platforms. Specific Background: Materials such as CrI₃ and Cr₂Ge₂Te₆ exhibit intrinsic ferromagnetism that can be tuned through mechanical strain and electron doping. Knowledge Gap: Previous studies mainly examined strain and doping separately, with limited integrated analysis of their combined role in magnetic phase stability. Aims: This study investigates quantum phases in two-dimensional magnetic monolayers using density functional theory, XXZ-Heisenberg modeling, and Monte Carlo simulations under strain and electron doping conditions. Results: CrI₃ maintains intrinsic ferromagnetism with an out-of-plane easy axis and a Curie temperature of 45 K, while 5% compressive strain increases magnetic anisotropy energy by approximately 47%. Electron doping in Cr₂Ge₂Te₆ increases the exchange constant from 6.874 meV to 10.202 meV and raises the Curie temperature from approximately 85 K to 123 K at 0.3 e/cell. Novelty: The study integrates electronic structure, magnetic anisotropy, exchange interactions, and thermal behavior within a unified computational framework. Implications: The findings provide theoretical guidance for developing thermally stable two-dimensional magnetic materials for spintronics and quantum devices.
Highlights:
• CrI₃ monolayers preserve intrinsic ferromagnetism with out-of-plane magnetic ordering at 45 K.• Compressive biaxial deformation increases magnetic anisotropy energy and stabilizes thermal magnetic behavior.• Electron carrier injection in Cr₂Ge₂Te₆ raises exchange coupling and Curie temperature to 123 K.
Keywords: Two-Dimensional Magnetic Materials, Quantum Phases, Density Functional Theory, Electron Doping; Monte Carlo Simulation
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