News Excerpt:

Researchers have identified a unique mechanism of electric polarization via magnetic ordering in a novel mineral named “MnBi2S4”, which can be useful for energy-efficient data storage.

About Magnetoelectric multiferroics material:

• Magnetoelectric multiferroics are a special class of materials popular among the research fraternity for their rarity and unique properties. 
• Interestingly, these materials can exhibit both magnetism and ferroelectricity simultaneously. 
• This dual property is particularly fascinating, as materials typically possess either magnetism or ferroelectricity. 
• Therefore, finding a single material with both properties is rare and valuable, especially for advanced technology applications like spintronics, electronic memory devices, and other electronic components like actuators and switches.

MnBi2S4:

• It is also known as mineral graţianite and belongs to the ternary manganese chalcogenide family. 
• On conducting a detailed study using high-resolution neutron diffraction, researchers identified distinct magnetic structures in the material, including a spin density wave and cycloidal and helical spin structures. 
• Importantly, they found that the last two spin structures induce ferroelectricity in the material.
• As per the new study, MnBi2S4, also known as centrosymmetric, undergoes magnetic ordering at low temperatures (27, 23, and 21.5 Kelvins). 
• Neutron diffraction was crucial in characterizing the different magnetic structures responsible for electric polarization at these temperatures.
• At 27 Kelvin, the researchers observed a spin density wave structure that did not break inversion symmetry or induced polarization. 
• However, as the temperature decreased to 23 Kelvin, a magnetic transition occurred, resulting in a cycloidal spin structure that did break inversion symmetry and induced polarization. 
• Further cooling to 21.5 Kelvin led to a helical structure, also breaking inversion symmetry and inducing polarization.

Significance of the new study:

• The significance of this finding lies in the strong coupling between magnetism and electric polarization. 
• The unique mechanism, driven by magnetic frustration, represents a breakthrough in magnetoelectric coupling.
• This discovery is particularly important as it has never been reported in the specific MnBi2S4 material before.

• The findings of this study could find applicability in the domain of energy-efficient data storage. 
  • Specifically, if the material possesses the ability to exhibit the same phenomena at room temperature, it could pave the way for energy-efficient manipulation of spin using small electric fields. 
• This could revolutionize data storage by reducing energy consumption during writing processes.
• Additionally, these findings can be helpful for the development of four-state logic memory system, providing additional degrees of freedom for device performance compared to the current binary logic systems.