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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
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Correlation-driven topological phase transition in 2D valleytronic materials: a mini-review
1School of Electronic Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121, China. sandongyuwang@163.com.
Physical Chemistry Chemical Physics : PCCP
|July 6, 2023
Summary
Electronic correlation and spin-orbit coupling influence 2D magnetic materials. Applying strain can induce topological phase transitions, creating novel valley-polarized quantum anomalous Hall insulators and half-valley-metals.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Electronic correlation and spin-orbit coupling (SOC) significantly impact the properties of 2D transition metal magnetic compounds.
- Magnetic anisotropy (MA) is crucial for determining magnetic, ferrovalley (FV), and topological characteristics in these 2D systems.
Purpose of the Study:
- To investigate the role of electronic correlation in inducing topological phase transitions in 2D valleytronic materials.
- To explore the creation of novel valley-polarized quantum anomalous Hall insulators (VQAHI) and half-valley-metals (HVM).
Main Methods:
- Density-functional theory (DFT) + U approach was employed.
- Analysis of electronic correlation effects on magnetic compounds like FeCl2 and VSi2P4.
Main Results:
- Out-of-plane MA enables topological phase transitions driven by electronic correlation, leading to VQAHI and HVM states.
- These transitions involve sign-reversible Berry curvature and band inversion between d orbitals.
- In-plane MA suppresses FV and nontrivial topological properties.
- Strain can induce these novel electronic states and topological phase transitions even when correlation strength is fixed.
Conclusions:
- Electronic correlation plays a vital role in realizing exotic topological states in 2D magnetic materials.
- Strain engineering offers a practical pathway to tune and achieve these novel electronic and topological properties.
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