Tuning Perpendicular Magnetic Anisotropy by Oxygen Octahedral Rotations in (La$_{1-x}$Sr$_{x}$MnO$_{3}$)/(SrIrO$_{3}$) Superlattices

Interface induced exchange bias effect in La$_{0.67}$Sr$_{0.33}$MnO$_3$/SrIrO$_3$ multilayer

Epitaxial superlattices of ferromagnetic/paramagnetic La$_{0.67}$Sr$_{0.33}$MnO$_3$/SrIrO$_3$ materials have been prepared on SrTiO$_3$ (100) substrate using pulse laser deposition technique. An unexpected onset of interface magnetic interaction has been observed around 40 K. Interestingly, magnetic exchange bias effect has been observed in both field cooled and zero field cooled magnetization loops, however, the shifting of loop is opposite in both measurements. Exchange bias field vanishes as temperature increases to interface magnetic ordering temperature. Moreover, exchange bias field is f…

Interplay of Spin-Orbit Interactions, Dimensionality, and Octahedral Rotations in Semimetallic SrIrO$_3$

We employ reactive molecular-beam epitaxy to synthesize the metastable perovskite SrIrO$_{3}$ and utilize {\it in situ} angle-resolved photoemission to reveal its electronic structure as an exotic narrow-band semimetal. We discover remarkably narrow bands which originate from a confluence of strong spin-orbit interactions, dimensionality, and both in- and out-of-plane IrO$_6$ octahedral rotations. The partial occupation of numerous bands with strongly mixed orbital characters signals the breakdown of the single-band Mott picture that characterizes its insulating two-dimensional counterpart, Sr…

3$d$-5$d$基La$_{0.67}$Ca$_{0.33}$MnO$_3$/SrIrO$_3$双层膜中的不对称磁电阻：单向各向异性的作用

Asymmetric magnetoresistance in 3$d$-5$d$ based La$_{0.67}$Ca$_{0.33}$MnO$_3$/SrIrO$_3$ bilayer: The role of unidirectional anisotropy

本研究通过实验揭示3d铁磁/5d重金属双层膜中界面磁耦合诱导的不对称磁电阻，归因于单向各向异性与自旋散射调控，为功能异质结构设计提供新见解。

A Resonant X-ray Scattering Study of Octahedral Tilt Ordering in LaMnO$_3$ and Pr$_{1-x}$Ca$_x$MnO$_3$

We report an x-ray scattering study of octahedral tilt ordering in the manganite series Pr$_{1-x}$Ca$_x$MnO$_3$ with x=0.4 and 0.25 and in LaMnO$_3$. The sensitivity to tilt ordering is achieved by tuning the incident x-ray energy to the L$_I$, L$_{II}$ and L$_{III}$ absorption edges of Pr and La, respectively. The resulting energy-dependent profiles are characterized by a dipole-resonant peak and higher energy fine structure. The polarization dependence is predominantly $σ$-to-$π$ and the azimuthal dependence follows a sin-squared behavior. These results are similar to those obtained in recen…

Influence of dopant concentration on the structure and physical properties of Nd$_{1-x}$Pb$_{x}$MnO$_{3}$ single crystals

The structure of Nd$_{1-x}$Pb$_{x}$MnO$_{3}$ crystals is determined by single crystal X-ray diffraction. Substitution of Pb at the Nd site results in structural phase change from tetragonal (x = 0.25) to cubic (x = 0.37). These changes are attributed to the progressive removal of inter-octahedral tilting and minimization of the octahedral distortion leading to a higher symmetry as doping concentration increases. While the unit cell volume of tetragonal structure ($\it{P4/mmm}$) is comparable to that of parent NdMnO$_{3}$, the volume of cubic unit cell ($\it{Pm\bar{3}m}$) is doubled. Electron d…

Lateral modulation of magnetic anisotropy in tricolor 3d-5d oxide superlattices

Manipulating magnetic anisotropy (MA) purposefully in transition metal oxides (TMOs) enables the development of oxide-based spintronic devices with practical applications. Here, we report a pathway to reversibly switch the lateral magnetic easy-axis via interfacial oxygen octahedral coupling (OOC) effects in 3d-5d tricolor superlattices, i.e. [SrIrO3,mRTiO3,SrIrO3,2La0.67Sr0.33MnO3]10 (RTiO3: SrTiO3 and CaTiO3). In the heterostructures, the anisotropy energy (MAE) is enhanced over one magnitude to ~106 erg/cm3 compared to La0.67Sr0.33MnO3 films. Moreover, the magnetic easy-axis is reversibly r…