Recent Progress in Flexible Multiferroics

Abstract

A great deal of interest has grown in both academia and industry toward flexible multiferroics in the recent years. The coupling of ferromagnetic properties with ferroelectric properties in multiferroic materials opens up many opportunities in applications such as magnetoelectric random access memories, magnetic field sensors, and energy harvesters. Multiferroic materials on a flexible platform bring an exciting opportunity for the next generation of consumer electronics owing to their unique characteristics of wearability, portability, and weight reduction. However, the fabrication of flexible multiferroic devices is still a great challenge due to various technical difficulties, including the requirement of high growth temperature of the oxide-based multiferroic materials, their lattice mismatch with the flexible substrates, and the brittleness of the functional layers. In this review article, we will discuss different methods of fabricating flexible or even freestanding oxide films to achieve flexible electronics. This article will address the benefits and challenges of each synthesis method in terms of interlayer interactions and growth parameters. Furthermore, the article will include an account of the possible bending limits of different flexible substrates without degrading the properties of the functional layer. Finally, we will address the challenges, opportunities, and future research directions in flexible multiferroics.

Electrical properties and Raman spectra in HoxMn1-xS solid solution

“…Modes Ag have the maximum intensity at frequencies ω = 220 cm -1 and 716 cm -1 and B3g (yz) at a frequency of 310 cm -1 . The main features observed in the spectrum at room temperature are the four bands centered around 200 cm -1 (R1), 340 cm -1 (R2), 450 cm -1 (R3) and 600 cm -1 (R4) [22]. These broad bands are seen in the insulating high-temperature phases of all the disordered manganites independent of the crystallographic symmetry.…”

Multifunctionality in Electrically Poled PMN–PT/Ni–Mn–In Multiferroic Heterostructure for Flexible Magnetic Field Sensing and Nonvolatile Memory Applications

“…26,27 An alternative to circumvent substrate clamping is the incorporation of thin film-based ME heterostructures on flexible substrates. 28 Additionally, this approach provides flexible ME devices for effective incorporation into flexible and wearable electronics where traditional Sibased ME devices cannot be integrated due to their rigid and brittle nature. Polyvinylidene fluoride, ultrathin glass, metal foils, and polyimide have already been utilized to fabricate flexible ME devices.…”

“…Recent attempts toward enhancing the performance of thin film-based ME devices have faced the hurdle of clamping effect imposed by the rigid substrate, which degrades the functional properties and ME coupling. , An alternative to circumvent substrate clamping is the incorporation of thin film-based ME heterostructures on flexible substrates . Additionally, this approach provides flexible ME devices for effective incorporation into flexible and wearable electronics where traditional Si-based ME devices cannot be integrated due to their rigid and brittle nature.…”

Magnetoelectric Functionality of Ni–Mn–In-Encapsulated AlN/Ni–Mn–In/Ni-Graded Heterostructure for Flexible Magnetic Field Sensor

“…The current studies have been devoted to low-cost and mechanically stable magnetic field sensors for room-temperature applications. The simplest approach for developing the flexible magnetic field sensing device is fabricating piezoelectric thin films on a flexible substrate. ,− ,, The frequently used flexible substrates are poly­(ether sulfone) (PES), ultrathin metal foils, plastic sheets, and polyimides. ,,,, Nickel (Ni) foil is a promising flexible substrate due to its low cost, high fracture strength, and large-area fabrication possibility. , However, the direct deposition of piezoelectric films on magnetostrictive metallic foils leads to weak ME coupling due to the thermal mismatch between the film and metallic foil, causing interfacial chemical reactions . Introducing the ferromagnetic layer between the piezoelectric film and metallic foil can provide additional interfacial strain.…”