Intrinsic quantum anomalous hall effect in a two-dimensional anilato-based lattice

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Chemistry

Background:

• The quantum anomalous Hall (QAH) effect is a quantum phenomenon with potential applications in low-power electronics.
• Realizing the QAH effect typically requires magnetic doping or external fields, posing challenges for practical applications.
• Metal-organic frameworks (MOFs) offer tunable structures and properties, making them promising candidates for novel electronic states.

Purpose of the Study:

• To theoretically predict and investigate the possibility of an intrinsic quantum anomalous Hall (QAH) state in a specific class of monolayer anilato-based metal-organic frameworks.
• To explore the underlying mechanism responsible for the QAH state and confirm its topological nature.
• To assess the potential of these materials as a platform for spintronic devices.

Main Methods:

• First-principles calculations were employed to model the electronic structure and properties of the proposed materials.
• Density Functional Theory (DFT) was used to determine the band structure, spin-orbit coupling effects, and topological invariants.
• Electron counting rules were applied to elucidate the origin of the intrinsic QAH state.

Main Results:

• An intrinsic QAH state was predicted in monolayer M2(C6O4X2)3 (M = Mn, Tc; X = F, Cl, Br, I) anilato-based metal-organic frameworks.
• Spin-orbit coupling was identified as the key mechanism opening a band gap of up to 18 meV at the Dirac point.
• Calculations confirmed nontrivial topological properties, including a nonzero Chern number, gapless edge states, and quantized Hall conductance.

Conclusions:

• Anilato-based metal-organic frameworks present a viable organic materials platform for realizing the intrinsic QAH effect.
• The absence of magnetic or charge doping requirements makes these materials highly desirable for developing energy-efficient spintronic devices.
• This research opens new avenues for designing next-generation topological electronic materials and devices.