Multiferroic materials: Why are they important for now and next generation?

Dr. Gopeshwar Dhar Dwivedi

Assistant Professor, Department of Physics, Faculty of Science, Kalinga University, Nava Raipur, Chhattisgarh

Introduction

In the world of materials science, multiferroic materials have emerged as a fascinating and promising class of materials with unique properties that have the potential to revolutionize various technological applications. These materials possess the rare combination of both ferroelectric and ferromagnetic properties, making them highly sought after for their ability to exhibit multiple orders of magnetization and polarization simultaneously. In this article, we will delve into the world of multiferroic materials, exploring their properties, applications, and the exciting potential they hold for future technologies.

Understanding multiferroic materials

Multiferroic materials are relatively new in the realm of condensed matter physics and materials science. In general perspective, multiferroic materials could display ferroelectric and ferromagnetic properties simultaneously in a single material.

Ferroelectricity: Ferroelectric materials exhibit a spontaneous electric polarization that can be switched by applying an external electric field. This property is essential in various electronic devices like capacitors, sensors, and non-volatile memory.

Ferromagnetism: Ferromagnetic materials possess a spontaneous magnetization that can be switched by an external magnetic field. These materials are used extensively in data storage, sensors, and electromagnets.

Multiferroic materials exhibit both of these properties simultaneously, making them incredibly versatile and appealing for a wide range of applications.

Types of Multiferroic Materials

There are two primary types of multiferroic materials:

1. Type-I Multiferroics:In these multiferroic materials, origins of magnetism and ferroelectricity are distinct. These multiferroic materials exhibit either weak or no cross-coupling between both order parameters.
2. Type-II Multiferroics:In these multiferroic materials, ferroelectricity develops due to the internal magnetic ordering of the system. These multiferroic materials usually possess significant cross-coupling between their order parameters and exhibit magneto-electric properties.

The coexistence of ferroelectric and ferromagnetic properties in multiferroic materials gives rise to magnetoelectric coupling. This property enables the manipulation of magnetization through an electric field and vice versa, opening up possibilities for novel device applications.

Applications of Multiferroic Materials

The distinctive properties of multiferroic materials have the potential to revolutionize various technological fields, including:

1. Spintronics: Multiferroic materials can be used in spintronic devices, where the electron’s spin is utilized for information storage and processing. The strong magnetoelectric coupling allows for efficient control of spin currents, leading to faster and more energy-efficient electronic devices.
2. Sensors: Multiferroic materials can be employed in advanced sensors and actuators, where their sensitivity to both electric and magnetic fields can enhance the performance of devices such as accelerometers and magnetometers.
3. Non-Volatile Memory: The coexistence of ferroelectricity and ferromagnetism in multiferroic materials makes them ideal candidates for non-volatile memory devices, which retain data even when the power is turned off.
4. Energy Conversion: Multiferroic materials are being investigated for energy harvesting applications, where they can convert mechanical vibrations or thermal gradients into electrical energy.
5. Next-Generation Electronics: Researchers are exploring multiferroic materials for the development of more efficient and compact electronic devices.

Challenges and Future Prospects

Despite their incredible potential, multiferroic materials also face several challenges, including the difficulty in finding materials that exhibit these properties at room temperature and the need for precise control over domain structures. We (researchers) are continuously trying to explore the novel synthesis methods and materials to overcome these challenges.

In conclusion, multiferroic materials represent a remarkable frontier in materials science, offering the promise of ground-breaking technological advancements across various fields. As research in this area continues to progress, we can anticipate exciting developments that will shape the future of electronics, sensors, and energy conversion technologies, ultimately leading to more efficient and versatile devices.

References:

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• A.Hill, Why Are There so Few Magnetic Ferroelectrics?J. Phys. Chem. B104, 6694-6709 (2000).
• Khomskii, Magnetism and ferroelectricity; why do they so seldom coexist?Bull. Am. Phys. Soc.C21.002 (2001).