Gradient Strain‐Induced Room‐Temperature Ferroelectricity in Magnetic Double‐Perovskite Superlattices

Abstract

Single-phase multiferroics suffer from a fundamental contradiction between polarity and magnetism in d 0 electronic configuration, motivating studies of unconventional ferroelectricity in magnetic oxides. However, low critical temperature and polarization still need to be overcome. Here, it is reported that the switchable polarization behavior at room temperature in [(La 2 NiMnO 6 )/(La 2 CoMnO 6 )] n double-perovskite magnetic superlattice films is achieved by engineering a microstructure with gradient strains, and the ferromagnetic Curie temperature did not show a rapid decrease. The synergy of gradient strains and superlattice components plays a decisive role in inducing ferroelectricity via the tilting or rotation of various oxygen octahedra. Such distortion responses to gradient strains are accompanied by slight magnetic fluctuations, maximizing the preservation of the initial magnetic exchange interactions, which alleviates the contradiction of multiferroic coexistence to a certain extent. This work confirms the room-temperature ferroelectricity in double-perovskite superlattices and provides a preferred strategy for confronting the difficulty of multiferroic coexistence in single-phase materials.

Experimental demonstration of tunable hybrid improper ferroelectricity in double-perovskite superlattice films

“…For simplicity, we adopt (002) pc instead while indexing, according to the pseudocubic (pc) notation 36 . The OP lattice constant c pc of the SL 10 is calculated as 3.848 Å, which corresponds to the OP compressive strain of − 0.88% compared to the average bulk value of LNMO and LCMO 37 . It should be noted that the strain relaxation process in superlattice films is effectively controlled by film thicknesses, as shown by the clear left shift of (002) pc peaks in the enlarged inset of XRD.…”

A Porous Multi‐Stimuli‐Responsive Liquid Crystal Elastomer Actuator Enabled by Mof Loading

“…In particular, a deformable and electrically responsive porous LCE filled with an ionic liquid (IL) was demonstrated to integrate the sensing and actuating functions. [18] To further develop porous LCEs, we raised a new question in the present study: can we use some sort of removable particles that not only serve as template for creating pores, but also have other exploitable functions, i.e., an active porogen. Our reflection led to the choice of a MOF, namely MIL-88A (MIL = Materials from Institute Lavoisier), for the following reasons: 1) The presence of MOF in LCE matrix creates molecular-or nanoscale pores, since MOF is porous material in itself.…”

An effective descriptor for the screening of electrolyte additives toward the stabilization of Zn metal anodes

“…4g and Table S2, ESI †). 38,[43][44][45][46][47][48][49][50][51] The interfacial kinetics of the Zn anode was evaluated by the rate performance of symmetric cells (Fig. 4e).…”