Correlation driven topological nodal ring ferromagnetic spin gapless semimetal: CsMnF₄

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Layered magnetic materials with topological properties are crucial for next-generation spintronic devices.
• Spin gapless semimetals offer 100% spin polarization, preventing spin leakage and enhancing device performance.

Purpose of the Study:

• Investigate the electronic and magnetic properties of the layered perovskite CsMnF4.
• Explore its potential as a topological nodal-ring spin gapless semimetal for spintronic applications.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• DFT + U method was used to study the effect of on-site Coulomb interaction (U).
• Spin-orbit coupling (SOC) was included to analyze magneto-crystalline anisotropy.

Main Results:

• CsMnF4 transitions from an insulating to a half-semimetallic state with decreasing U.
• Topological nodal-ring dispersion with Mexican hat-like features emerged at U = 2.5 eV.
• In-plane ferromagnetism and significant transport anisotropy were observed.

Conclusions:

• CsMnF4 exhibits robust topological properties and high Fermi velocities comparable to graphene.
• The material shows potential for high-speed spin electronic and memory devices.
• Preservation of nodal rings is possible despite broken time-reversal symmetry in magnetic systems.