23.2 Coupling mechanisms in piezo-magnetoelectric composites
2 min read•august 9, 2024
Piezo-magnetoelectric composites combine piezoelectric and magnetic materials to create unique coupling effects. These materials can convert between electrical, mechanical, and magnetic energies, opening up exciting possibilities for sensors and energy harvesting devices.
Coupling mechanisms in these composites include strain-mediated and charge-mediated interactions. Understanding these mechanisms is crucial for optimizing composite performance and developing new applications in fields like electronics and energy technology.
Coupling Mechanisms
Strain-Mediated and Charge-Mediated Coupling
Top images from around the web for Strain-Mediated and Charge-Mediated Coupling
First-time synthesis of a magnetoelectric core–shell composite via conventional solid-state ... View original
Is this image relevant?
First-time synthesis of a magnetoelectric core–shell composite via conventional solid-state ... View original
Is this image relevant?
1 of 1
Top images from around the web for Strain-Mediated and Charge-Mediated Coupling
First-time synthesis of a magnetoelectric core–shell composite via conventional solid-state ... View original
Is this image relevant?
First-time synthesis of a magnetoelectric core–shell composite via conventional solid-state ... View original
Is this image relevant?
1 of 1
- occurs when transfers between piezoelectric and magnetostrictive phases
- converts electrical energy into mechanical strain
- converts mechanical strain into
- involves accumulation of charges at interfaces between phases
- create electric fields that influence magnetic properties of adjacent layers
- Both mechanisms contribute to overall in composites
Exchange Bias and Interfacial Effects
- coupling results from interaction between ferromagnetic and at interfaces
- Causes shift in magnetic hysteresis loop, enhancing magnetoelectric response
- include formation of intermediate phases or defects at boundaries between piezoelectric and magnetic components
- These effects can significantly alter coupling strength and overall composite performance
- and at interfaces play crucial roles in determining
Magnetoelectric Effects
Magnetoelectric Coefficient and Direct Effect
- quantifies strength of coupling between electric and magnetic fields in a material
- Expressed as change in per unit (V/cm·Oe)
- involves generation of electric polarization in response to applied magnetic field
- Occurs when magnetic field induces strain in magnetostrictive phase, transferred to piezoelectric phase
- Piezoelectric phase converts strain into electric polarization, measurable as voltage or charge
Converse Magnetoelectric Effect and Applications
- describes induced by applied electric field
- Electric field causes strain in piezoelectric phase, transferred to magnetostrictive phase
- Magnetostrictive phase converts strain into change in magnetization
- Enables electrical control of magnetic properties in composite materials
- Applications include , , and
Key Terms to Review (24)
Accumulated Charges: Accumulated charges refer to the build-up of electric charge within a material, which can occur due to external mechanical stress or deformation. In the context of piezo-magnetoelectric composites, these charges are crucial as they result from the coupling between mechanical forces and electric fields, enabling energy harvesting from mechanical vibrations. This charge accumulation allows for efficient energy conversion and storage, making it essential in applications like sensors and actuators.
Antiferromagnetic Materials: Antiferromagnetic materials are a class of materials in which adjacent magnetic moments align in opposite directions, resulting in no net macroscopic magnetization. This unique arrangement occurs due to exchange interactions at the atomic level, where the spins of neighboring atoms or ions cancel each other out, leading to a complex magnetic behavior. These materials play a significant role in various applications, particularly in piezo-magnetoelectric composites, where their properties can be exploited for energy harvesting and advanced electronic devices.
Applied magnetic field: An applied magnetic field is an external magnetic field that is intentionally introduced into a system to influence the behavior of materials or devices within that system. In the context of piezo-magnetoelectric composites, the applied magnetic field plays a critical role in enhancing the interaction between piezoelectric and magnetic phases, which can lead to improved energy harvesting capabilities and functionality in various applications.
Change in Magnetization: Change in magnetization refers to the alteration in the magnetic properties of a material due to external influences, such as mechanical stress, magnetic field variation, or temperature changes. This change is particularly important in the context of piezo-magnetoelectric composites, where the coupling between mechanical and magnetic domains can generate electric energy, thus allowing for energy harvesting applications.
Charge-mediated coupling: Charge-mediated coupling refers to the interaction mechanism in piezo-magnetoelectric composites where the electric charge generated by piezoelectric materials influences the magnetic response of magnetostrictive materials. This coupling relies on the transfer of electrical energy between the two types of materials, allowing for efficient energy conversion. Understanding this mechanism is crucial for enhancing the performance of devices that rely on both piezoelectric and magnetostrictive properties.
Chemical Bonding: Chemical bonding refers to the attraction between atoms that enables the formation of chemical compounds. This interaction can be due to the sharing or transferring of electrons, leading to the establishment of ionic, covalent, or metallic bonds. In the context of piezo-magnetoelectric composites, understanding chemical bonding is crucial as it influences material properties, including electrical and mechanical performance.
Converse magnetoelectric effect: The converse magnetoelectric effect refers to the phenomenon where an applied magnetic field induces an electric polarization in a material, typically in magnetoelectric materials. This effect highlights the interaction between magnetic and electric properties, allowing for the conversion of magnetic energy into electrical energy, which is crucial for the development of advanced energy harvesting devices.
Coupling Efficiency: Coupling efficiency refers to the effectiveness with which energy is transferred between different energy conversion mechanisms, specifically in piezo-magnetoelectric composites. This concept is crucial for understanding how well the piezoelectric and magnetoelectric materials work together to convert mechanical or magnetic energy into electrical energy, impacting the overall performance of energy harvesting systems. Higher coupling efficiency indicates better energy transfer and utilization, which is essential for optimizing the design and functionality of these composites.
Direct magnetoelectric effect: The direct magnetoelectric effect refers to the phenomenon where a material exhibits a change in electric polarization when subjected to a magnetic field. This effect is particularly important in piezo-magnetoelectric composites, where the interaction between magnetic and electric orders can be harnessed for energy harvesting and sensor applications. Understanding this effect is crucial for optimizing the performance of devices that combine both piezoelectric and magnetoelectric materials, allowing for enhanced functionality in various applications.
Electric Polarization: Electric polarization is the process by which a material develops an electric dipole moment in response to an external electric field, leading to a separation of positive and negative charges within the material. This phenomenon plays a crucial role in understanding how materials respond to electric fields, influencing their electrical and mechanical properties, especially in magnetoelectric and piezoelectric contexts.
Energy Harvesters: Energy harvesters are devices that capture and convert ambient energy from the environment into usable electrical energy. They play a crucial role in powering small electronic devices, sensors, and systems without the need for batteries or direct power sources, making them highly beneficial for sustainable energy applications.
Exchange bias: Exchange bias is a phenomenon that occurs in magnetic materials when a ferromagnet is in contact with an antiferromagnet, leading to a shift in the magnetic hysteresis loop. This interaction results in the modification of the magnetization direction and coercivity of the ferromagnet, which is crucial for enhancing the performance of piezo-magnetoelectric composites. The exchange bias effect plays a significant role in coupling mechanisms by allowing the piezoelectric and magnetic properties to interact more effectively.
Ferromagnetic materials: Ferromagnetic materials are substances that exhibit strong magnetic properties due to the alignment of their magnetic dipoles. These materials, like iron, cobalt, and nickel, have domains that can be magnetized in the presence of an external magnetic field, allowing them to retain their magnetization even after the field is removed. This property is significant in applications like piezo-magnetoelectric composites, where the interaction between electric and magnetic fields is crucial for energy harvesting.
Interfacial Effects: Interfacial effects refer to the phenomena that occur at the boundaries between different materials, particularly within composites. These effects are crucial in determining the overall performance and functionality of piezo-magnetoelectric composites, influencing their mechanical and electrical properties through interactions at the interface.
Magnetic field changes: Magnetic field changes refer to the variations in the intensity and direction of a magnetic field over time. In the context of piezo-magnetoelectric composites, these changes can induce electrical signals, making them vital for energy harvesting applications. The interplay between mechanical stress and magnetic field alterations enables the conversion of mechanical energy into electrical energy, thereby enhancing the performance of these composites.
Magnetic field sensors: Magnetic field sensors are devices that detect and measure magnetic fields, often converting this information into electrical signals for analysis or control. These sensors play a crucial role in various applications, including navigation, motion detection, and energy harvesting systems, particularly in piezo-magnetoelectric composites where the interaction between mechanical stress and magnetic fields is utilized.
Magnetoelectric coefficient: The magnetoelectric coefficient is a parameter that quantifies the coupling between magnetic and electric fields in magnetoelectric materials. It indicates how effectively a material can convert magnetic energy into electrical energy, or vice versa, and is crucial for the performance of piezo-magnetoelectric composites. Understanding this coefficient helps in optimizing energy harvesting devices that utilize both piezoelectric and magnetoelectric properties.
Magnetoelectric effect: The magnetoelectric effect refers to the interaction between magnetic and electric fields within certain materials, allowing them to generate an electric charge in response to a magnetic field or vice versa. This phenomenon is fundamental to understanding how magnetoelectric materials can be used in various applications, particularly in energy harvesting systems that combine magnetic and electrical properties to convert mechanical energy into usable electrical energy.
Magnetostrictive phase: The magnetostrictive phase refers to a material state where the dimensions of the material change in response to an applied magnetic field. This phenomenon is significant in piezo-magnetoelectric composites as it enables the coupling of mechanical and magnetic responses, leading to efficient energy conversion and enhanced performance in devices that harness both piezoelectric and magnetostrictive properties.
Mechanical Strain: Mechanical strain refers to the deformation that occurs in a material when an external force is applied, leading to changes in its shape or size. This deformation is crucial in understanding how materials respond to stress and is directly related to the generation of electrical charges in piezoelectric materials, thereby connecting to energy conversion processes and electromechanical interactions.
Multiferroic memory devices: Multiferroic memory devices are advanced memory systems that utilize materials exhibiting both ferroelectric and magnetic order, enabling them to store data efficiently and with low energy consumption. These devices leverage the unique properties of multiferroic materials, allowing for non-volatile data storage that can be accessed and manipulated through electric and magnetic fields, creating potential for faster and more efficient computing technologies.
Piezoelectric Phase: The piezoelectric phase refers to the material state in which certain substances generate an electric charge in response to mechanical stress. This property is crucial in piezo-magnetoelectric composites, where the interaction between piezoelectric and magnetic materials enables energy conversion through mechanical deformation, enhancing device performance and efficiency.
Strain-mediated coupling: Strain-mediated coupling refers to the interaction between mechanical strain and the electrical response in materials, particularly in piezoelectric and magnetoelectric composites. This coupling mechanism enables the conversion of mechanical energy into electrical energy or vice versa, through the deformation of materials that exhibit both piezoelectric and magnetostrictive properties. The efficiency of energy harvesting in these composites heavily relies on the effectiveness of this coupling.
Surface Roughness: Surface roughness refers to the texture of a surface characterized by the presence of irregularities and deviations from a perfectly smooth state. In the context of energy harvesting, particularly in piezo-magnetoelectric composites, surface roughness plays a significant role in affecting the mechanical interlocking and the coupling efficiency between different materials, impacting their overall performance and energy conversion capabilities.