Giant exchange bias in the single-layered Ruddlesden-Popper perovskite SrLaCo0.5Mn0.5O4

Abstract

Keywords: exchange bias, cluster spin glass, magnetic memory effect, density functional theory Exchange bias (EB) as large as ~5.5 kOe is observed in SrLaCo0.5Mn0.5O4 which is the highest ever found in any layered transition metal oxides including Ruddlesden-Popper series. Neutron diffraction measurement rules out long-range magnetic ordering and together with dc magnetic measurements suggest formation of short-range magnetic domains. AC magnetic susceptibility, magnetic memory effect and magnetic training effect confirm the system to be a cluster spin glass. By carrying out density functional calculations on several model configurations, we propose that EB is originated at the boundary between Mn-rich antiferromagnetic and Co-rich ferromagnetic domains at the sub-nanoscale. Reversal of magnetization axis on the Co-side alters the magnetic coupling between the interfacial Mn and Co spins which leads to EB. Our analysis infers that the presence of competing magnetic interactions is sufficient to induce exchange bias and thereby a wide range of materials exhibiting giant EB can be engineered for designing novel magnetic memory devices.

Giant exchange bias effect in Ruddlesden-Popper oxides SrLaFe0.25+xMn0.25Co0.5−xK1, Das2, Lekshmi3 et al. 2020Phys. Rev. BSelf Cite9000View full textAdd to dashboardCite

“…The refined lattice parameters, unit cell volume, atomic coordinates, and reliability factors of both samples are given in Table I; the equatorial and apical oxygens are represented as O1 and O2, respectively. Obtained refinement parameters are comparable with single-layered RP compounds [17,23]. The Rietveld refined XRD patterns for FMC1 and FMC2 are shown in Figs.…”

“…Recently, our group reported a giant EB field of ∼5.5 kOe in the single-layered RP system SrLaCo 0.5 Mn 0.5 O 4 (SLCMO), for which a low temperature glassy magnetic transition (T C2 ∼ 50 K) along with a ferromagnetic phase transition (at T C1 ∼ 150 K) were observed [17]. The perovskite analog of SLCMO is La 2 CoMnO 6 , which is a FM double perovskite.…”

B-site order/disorder in A2BB′O6 and its correlation with their magnetic property

“…, where H L is the left coercive field while H R is the right coercive field [134,135]. For PCMS25, H SEB E was found to be around 0.2053 T and H SEB C around 0.2360 T, which is pretty high.…”

Double glassy states and large spontaneous and conventional exchange bias in La1.5Ca0.5CoFeO6 ferrimagnetic double perovskite

“…respectively, where M R1 and M R2 are the two intercepts of magnetization axis [5,54,55]. The vertical and horizontal shifts in M-H curves may also occur due to unsaturated minor loop effect [56].…”