Multiferroic magnetoelectric composite systems such as ferromagnetic-ferroelectric heterostructures have recently attracted an ever-increasing interest and provoked a great number of research activities, driven by profound physics from coupling between ferroelectric and magnetic orders, as well as potential applications in novel multifunctional devices, such as sensors, transducers, memories, and spintronics. In this Review, we try to summarize what remarkable progress in multiferroic magnetoelectric composite systems has been achieved in most recent few years, with emphasis on thin films; and to describe unsolved issues and new device applications which can be controlled both electrically and magnetically.

Recent Progress in Multiferroic Magnetoelectric Composites: from Bulk to Thin Films

An insight into the analogies, state-of-the-art technologies, concepts, and prospects under the umbrella of perovskite materials (both inorganic-organic hybrid halide perovskites and ferroelectric perovskites) for future multifunctional energy conversion and storage devices is provided. Often, these are considered entirely different branches of research; however, considering them simultaneously and holistically can provide several new opportunities. Recent advancements have highlighted the potential of hybrid perovskites for high-efficiency solar cells. The intrinsic polar properties of these materials, including the potential for ferroelectricity, provide additional possibilities for simultaneously exploiting several energy conversion mechanisms such as the piezoelectric, pyroelectric, and thermoelectric effect and electrical energy storage. The presence of these phenomena can support the performance of perovskite solar cells. The energy conversion using these effects (piezo-, pyro-, and thermoelectric effect) can also be enhanced by a change in the light intensity. Thus, there lies a range of possibilities for tuning the structural, electronic, optical, and magnetic properties of perovskites to simultaneously harvest energy using more than one mechanism to realize an improved efficiency. This requires a basic understanding of concepts, mechanisms, corresponding material properties, and the underlying physics involved with these effects.

Mutual Insight on Ferroelectrics and Hybrid Halide Perovskites: A Platform for Future Multifunctional Energy Conversion.

Magnetocaloric effect: From materials research to refrigeration devices

A2B′B″O6 perovskites: A review

Electrocaloric materials for future solid-state refrigeration technologies

Multiferroic Bi0.95La0.05Fe0.7Sc0.3O3 (BLFS) thin films with different thicknesses have been prepared on (1 0 0) LaAlO3 (LAO) substrates using a sol–gel process and annealed in N2 ambient at 650°C for 5 min. From the X-ray diffraction (XRD) analysis, it was observed that BLFS thin films had (h 0 0)-preferred orientation for the film thickness 63, 125, 186, and 240 nm and became isotropic thereafter. The films developed in-plane epitaxial growth with respect to the substrate. The surface morphology became denser and the surface roughness increased as thickness increased up to 241 nm. The highest dielectric constant observed for the 241 nm thick BLFS film too. No prominent of the leakage current density observed for the film thickness up to 241 nm. However, two fold increase in the leakage current density observed for the film thickness 382 nm. For the BLFS films with thickness 241 nm, we observed the highest dielectric constant (e) value of 1675 and remnant polarization (Pr) polarization value of 52 μC/cm2 using a sol–gel spin coating process.

Thickness effects on the epitaxial nature of the single-phase multiferroic thin films

Ba2LaTaO6 is prepared by solid state reaction of a stoichiometric mixture of BaCO3, La2O3, and Ta2O5 (1350 °C, 6 h).

Electronic Structure and Electrical Properties of Ba2LaTaO6.

Functional Nanoceramics A Brief Review on Structure Property Evolutions of Advanced Functional Ceramics Processed Using Microwave and Conventional Techniques

The structural and magnetic properties of a double perovskite oxide Ba 2 CeSbO 6 (BCSO) synthesized by solid state reaction technique have been investigated. The Rietveld refinement of the X-ray diffraction pattern of BCSO suggests the monoclinic crystal structure at room temperature with P2 1 /n space group. The vibrational properties of BCSO are investigated by the Fourier transform Infrared and Raman spectroscopy. The Raman spectrum confirms the B-site ordering of cations in BCSO. The temperature dependent magnetic susceptibility data in the field cooled mode show the anti-ferromagnetic behaviour of BCSO below 59 K. The core level X-ray photoemission (XPS) spectrum of Ce-3d and Sb-3d states confirms the presence of multiple oxidation states of these cations. The presence of both the Ce 3+ and Ce 4+ ions in BCSO gives the 4f 4−δ intermediate valence state which may reduce the effective magnetic moment with respect to the system having single valence Ce 3+ ion.

Structural and Magnetic Properties of Double Perovskite Oxide Ba2CeSbO6.

This article was originally published online on 31 March 2015 with an incorrect author’s address. The address is correct
as it appears above. All online versions were corrected on 3 April 2015 and the address was correct as it appeared in the printed version of the journal.

Santiranjan Shannigrahi

Papers

Thickness effects on the epitaxial nature of the single-phase multiferroic thin films

Electronic Structure and Electrical Properties of Ba2LaTaO6.

Functional Nanoceramics A Brief Review on Structure Property Evolutions of Advanced Functional Ceramics Processed Using Microwave and Conventional Techniques

Structural and Magnetic Properties of Double Perovskite Oxide Ba2CeSbO6.

Ferroelectric capped magnetization in multiferroic PZT/LSMO tunnel junctions (vol 106, 132901, 2015)