Exchange bias in LaNiO3–LaMnO3 superlattices

Abstract

The wide spectrum of exotic properties exhibited by transition-metal oxides stems from the complex competition between several quantum interactions. The capacity to select the emergence of specific phases at will is nowadays extensively recognized as key for the design of diverse new devices with tailored functionalities. In this context, interface engineering in complex oxide heterostructures has developed into a flourishing field, enabling not only further tuning of the exceptional properties of these materials, but also giving access to hidden phases and emergent physical phenomena. Here we demonstrate how interfacial interactions can induce a complex magnetic structure in a non-magnetic material. We specifically show that exchange bias can unexpectedly emerge in heterostructures consisting of paramagnetic LaNiO3 (LNO) and ferromagnetic LaMnO3 (LMO). The observation of exchange bias in (111)-oriented LNO-LMO superlattices, manifested as a shift of the magnetization-field loop, not only implies the development of interface-induced magnetism in the paramagnetic LNO layers, but also provides us with a very subtle tool for probing the interfacial coupling between the LNO and LMO layers. First-principles calculations indicate that this interfacial interaction may give rise to an unusual spin order, resembling a spin-density wave, within the LNO layers.

Orbital polarization in strainedLaNiO3: Structural distortions and correlation effects

“…Furthermore, these structures exhibit novel behavior not found in their bulk counterparts. [1][2][3][4][5][6] The family of rare-earth nickelates, 7,8 RNiO 3 , has attracted particular attention in this context. Indeed, this class of materials has a rich phase diagram displaying a metal-to-paramagnetic-insulator, as well as a metal-tomagnetic-insulator transitions.…”

Compensated Ferrimagnetic Tetragonal Heusler Thin Films for Antiferromagnetic Spintronics

“…[23] The achievement of EB up to room temperature in the present bilayer films is an important step towards practical applications. Although exchange bias has been studied in some unconventional systems, such as, a ferromagnet/spin glass [24] , a ferromagnet/paramagnet [25] and a natural mineral [26] , the present exchange bias from ferrimagnet/compensated ferrimagnet is the first of its kind and has significant potential for technological applications. The flexible nature of Heusler materials to achieve tunable magnetizations, and anisotropies within closely matched materials provides a new direction to the growing field of antiferromagnetic spintronics.…”

Magneto-Plasmons in Periodic Nanoporous Structures

“…Recent investigations indicate that active magneto-plasmonic nanomaterials formed by noble metals and magnetic metals can improve the interaction between magnetic field, electric field, electromagnetic waves and the localized surface plasmon resonance (LSPR), leading to applications for efficient switching and transmission of electrical, magnetic, optical and acoustic signals based on active plasmonics 1,2,5,23,[36][37][38] . They hold promise for applications in spintronics, laser gyro, electromagnetic shielding, multi-mode biological probes, efficient photovoltaic cells, magneto-optical data storage and retrieval and nonreciprocal devices (e.g., magneto-optical isolators and circulators) 1,2,5,23,36,39,40 .The magneto-optical properties and the related proximity effect rely on the detailed morphology of each component and the dielectric properties of the media 2,23,36 . The correlation between these parameters and their magnetic properties, surface plasmon resonances and related magneto-optical properties has not been wellcharacterized, even though some progress has been achieved 1,2,4,5,8,23,[30][31][32] .…”

“…Recent investigations indicate that active magneto-plasmonic nanomaterials formed by noble metals and magnetic metals can improve the interaction between magnetic field, electric field, electromagnetic waves and the localized surface plasmon resonance (LSPR), leading to applications for efficient switching and transmission of electrical, magnetic, optical and acoustic signals based on active plasmonics 1,2,5,23,[36][37][38] . They hold promise for applications in spintronics, laser gyro, electromagnetic shielding, multi-mode biological probes, efficient photovoltaic cells, magneto-optical data storage and retrieval and nonreciprocal devices (e.g., magneto-optical isolators and circulators) 1,2,5,23,36,39,40 .…”

“…it is difficult to guarantee homogeneity of composition, structure and morphology by conventional preparation methods [27][28][29][30]42 This makes it difficult to identify the intrinsic proximity effects from the nanostructures and associated inter-particle interactions, which are necessary for precisely addressing the relationship between structures and their properties for high performance 2,39 . Therefore, it is essential either to characterize single nanostructures or to develop controlled fabrication processes for size homogeneity [26][27][28][29][30][31][32][33][34]42 .…”