Optically Controlled Magnetization and Magnetoelectric Effect in Organic Multiferroic Heterojunction

Abstract

The organic multiferroic effect receives increasing attention in organic electronics. Recently, the renaissance of organic multiferroics has yielded in a deep understanding of organic magnetism and magnetoelectric coupling. Here, through fabricating polythiophene nanowire/CH3NH3PbBr3 multiferroic heterojunction, the origin of organic magnetism, optically controlled magnetization, and magnetoelectric coupling with optical approach is studied. Specifically, the optical approach utilizes double beam 355 and 607 nm excitations to separately operate the CH3NH3PbBr3 and polythiophene nanowire layers. This double‐beam‐light approach allows to elucidate the effects of photogenerated charges on organic magnetism and magnetoelectric coupling effect. It is found that magnetization and magnetoelectric coupling of polythiophene nanowire/CH3NH3PbBr3 heterojunction can be effectively tuned through the photoexcitation of CH3NH3PbBr3, rather than photoexcitation of polythiophene nanowire phase, which has been further confirmed by electron spin resonance. Furthermore, the dominated factors are discussed to reveal room‐temperature magnetization in organics. This work provides a strategy for optically controlled organic magnetism and magnetoelectric effect in charge transfer heterojunction.

3D Organic–Inorganic Perovskite Ferroelastic Materials with Two Ferroelastic Phases: [Et3P(CH2)2F][Mn(dca)3] and [Et3P(CH2)2Cl][Mn(dca)3]

“…Current studies on multiferroics are focusing on the magnetoelectric effect by coupling ferroelectricity and ferromagnetism. For example, the multiferroic effects including heterojunction, magnetoelectric, and magnetism coupling effect could be selectively tuned by external light in polythiophene nanowire/CH 3 NH 3 PbBr 3 . Additionally, a series of metal–organic frameworks (MOFs) based on formate ligands have been reported with interesting multiferroics .…”

“…For example, the multiferroic effects including heterojunction,m agnetoelectric, and magnetism coupling effect could be selectively tuned by external light in polythiophene nanowire/CH 3 NH 3 PbBr 3 . [4] Additionally,aseries of metal-organic frameworks (MOFs) based on formate ligandsh ave been reported with interesting multiferroics. [5] In these compounds, the cross-couplingb etween magnetic and electric arises from two different active "sublattices"i nt he perovskite structure: i) the frameworks connected by formate ligand display cooperative magnetism at low temperature;i i) the organic cationso ccupying the A-site of the perovskite architecture experience an order-disorder phase transitionw ith dielectric constant change.…”

Strategies and applications of generating spin polarization in organic semiconductors

“…Currently, multiple charge-transfer complex systems, such as P3HT:PCBM, SWCNT-C 60 , C 60 :SWCNT:PVDF, and P3HT-nW:CH 3 NH 3 PbBr 3 have been observed to exhibit multiferroic properties. 173,174,177 In fact, remarkable progress has been made in organic charge-transfer complexes with ferromagnetic and multiferroic properties. However, compared to single components, this system will have more complex spin interactions, and there are still many unanswered questions regarding the source of spontaneous spin polarization and the coupling mechanism.…”

Enhanced magneto-electric effect in manganite tricolor superlattice with artificially broken symmetry

“…At present, many different approaches are used to increase the ME coupling, e.g., chemical doping, highly oriented epitaxial films, or heterojunction composite films composed of ferroelectric and ferromagnetic layers. [21][22][23][24] Among these approaches, superlattices (SLs) can be viable candidates. They are composed of thin layers of two or more different compositions that are stacked in a specific sequence.…”