Highly Tunable Perpendicular Magnetic Anisotropy and Anisotropic Magnetoresistance in Ru-Doped La_(0.67)Sr_(0.33)MnO_(3)Epitaxial Films

As a prototypical half-metallic ferromagnet,La_(0.67)Sr_(0.33)MnO_(3)(LSMO)has been extensively studied due to its versatile physical properties and great potential in spintronic applications.However,the weak perpendicular magnetic anisotropy(PMA)limits the controllability and detection of magnetism in LSMO,thus hindering the realization of oxide-based spintronic devices with low energy consumption and high integration level.Motivated by this challenge,we develop an experimental approach to enhance the PMA of LSMO epitaxial films.By cooperatively introducing 4d Ru doping and a moderate compressive strain,the maximum uniaxial magnetic anisotropy in Ru-doped LSMO can reach 3.0×10^(5)J/m^(3)at 10 K.Furthermore,we find a significant anisotropic magnetoresistance effect in these Ru-doped LSMO films,which is dominated by the strong PMA.Our findings offer an effective pathway to harness and detect the orientations of magnetic moments in LSMO films,thus promoting the feasibility of oxide-based spintronic devices,such as spin valves and magnetic tunnel junctions.

Extended phase diagram of La_(1-x)Ca_(x)MnO_(3)by interfacial engineering

The interfacial enhanced ferromagnetism in maganite/ruthenate system is regarded as a promising path to broaden the potential of oxide-based electronic device applications.Here,we systematically studied the physical properties of La_(1-x)Ca_(x)MnO_(3)/SrRuO_(3)superlattices and compared them with the La1-x Cax MnO_(3)thin films and bulk compounds.The La_(1-x)Ca_(x)MnO_(3)/SrRuO_(3)superlattices exhibit significant enhancement of Curie temperature(TC)beyond the corresponding thin films and bulks.Based on these results,we constructed an extended phase diagram of La_(1-x)Ca_(x)MnO_(3)under interfacial engineering.We considered the interfacial charge transfer and structural proximity effects as the origin of the interfaceinduced high TC.The structural characterizations revealed a pronounced increase of B-O-B bond angle,which could be the main driving force for the high TCin the superlattices.Our work inspires a deeper understanding of the collective effects of interfacial charge transfer and structural proximity on the physical properties of oxide heterostructures.

Asymmetric interfaces and high-TC ferromagnetic phase in La_(0.67)Ca_(0.33)MnO_(3)/SrRuO_(3)superlattices

Interfacial magnetism in functional oxide heterostructures not only exhibits intriguing physical phenomena but also implies great potential for device applications.In these systems,interfacial structural and electronic reconstructions are essential for improving the stability and tunability of the magnetic properties.In this work,we constructed ultra-thinLa_(0.67)Ca_(0.33)MnO_(3)/SrRuO_(3)(SRO)layers into superlattices,which exhibited a robust ferromagnetic phase.The high Curie temperature(TC)reaches 291 K,more than 30 K higher than that of bulk LCMO.We found that the LCMO/SRO superlattices consisted of atomically-sharp and asymmetric heterointerfaces.Such a unique interface structure can trigger a sizable charge transfer as well as a ferroelectric-like polar distortion.These two interfacial effects cooperatively stabilized the high-T_(C)ferromagnetic phase.Our results could pave a promising approach towards effective control of interfacial magnetism and new designs of oxide-based spintronic devices.