Magnetism and spin exchange coupling in strained monolayer CrOCl

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Chemistry

Background:

• Monolayer chromium oxychloride (CrOCl) exhibits interesting magnetic properties.
• Understanding strain effects is crucial for tailoring material functionalities.

Purpose of the Study:

• To systematically investigate the effects of uniaxial strain on the magnetism and spin exchange coupling of monolayer CrOCl.
• To elucidate the mechanisms behind strain-induced magnetic transitions and Curie temperature enhancement.

Main Methods:

• First-principles calculations were employed to study monolayer CrOCl under varying strain conditions.
• Analysis of spin exchange coupling was performed using the Goodenough-Kanamori-Anderson (GKA) and Bethe-Slater Interaction (BSI) rules.

Main Results:

• Uniaxial strain along the a- or b-axis can switch the magnetic ground state between ferromagnetic (FM) and antiferromagnetic (AFM).
• Applying strain significantly enhances the Curie temperature (T_C).
• Strain-dependent magnetic transitions are governed by the competition between direct cation-cation and indirect cation-anion-cation superexchange interactions.

Conclusions:

• Monolayer CrOCl's magnetic state is highly sensitive to external strain.
• The critical distances for antiferromagnetic-ferromagnetic transitions differ along the a- and b-axis directions.
• The tunable magnetic coupling in strained CrOCl makes it a promising material for spintronic devices.