A controllable robust multiferroic GaTeCl monolayer with colossal 2D ferroelectricity and desirable...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid State Chemistry

Background:

• Two-dimensional (2D) materials are extensively researched for novel electronic and magnetic properties.
• Multiferroic materials, exhibiting multiple ferroic orders, are crucial for advanced device applications.
• Exploring new 2D multiferroics with enhanced properties remains a key research objective.

Purpose of the Study:

• To investigate the potential of the Gallium telluride chloride (GaTeCl) monolayer as a two-dimensional (2D) multiferroic material.
• To analyze its mechanical, ferroelectric, ferroelastic, piezoelectric, and optical properties.
• To assess its stability and potential for exfoliation and device integration.

Main Methods:

• First-principles calculations were employed to study the electronic and structural properties.
• Phonon spectrum analysis and molecular dynamic simulations were used to confirm dynamic and mechanical stability.
• Calculations of elastic moduli and cleavage energy were performed to assess mechanical feasibility.

Main Results:

• GaTeCl monolayer demonstrates dynamic and mechanical stability with giant mechanical anisotropy.
• It exhibits robust in-plane ferroelectricity (578 pC m-1) and ferroelasticity with high energy barriers.
• Mechanical stress can controllably tune ferroelectric polarization and induce a phase transition from indirect to direct bandgap.

Conclusions:

• GaTeCl monolayer is a promising 2D multiferroic material with exceptional properties.
• Its robust ferroelasticity, ferroelectricity, giant piezoelectricity, and optical second harmonic generation highlight its potential.
• The material's mechanical controllability and multi-functional characteristics make it suitable for high-performance applications.