Controllable Itinerant Ferromagnetism in Weakly Correlated 5d SrIrO₃

Abstract

The weakly correlated nature of 5d oxide SrIrO3 determines its rare ferromagnetism, and the control of its magnetic order is even less studied. Tailoring structure distortion is currently a main route to tune the magnetic order of 5d iridates, but only for the spatially confined insulating counterparts. Here, we have realized ferromagnetic order in metallic SrIrO3 by construction of SrIrO3/ferromagnetic-insulator (LaCoO3) superlattices, which reveal a giant coercivity of ∼10 T and saturation field of ∼25 T with strong perpendicular magnetic anisotropy. The Curie temperature of SrIrO3 can be controlled by engineering interface charge transfer, which is confirmed by Hall effect measurements collaborating with EELS and XAS. Besides, the noncoplanar spin texture is captured, which is caused by interfacial Dzyaloshinskii-Moriya interactions as well. These results indicate controllable itinerant ferromagnetism and an emergent topological magnetic state in strong spin–orbit coupled semimetal SrIrO3, showing great potential to develop efficient spintronic devices.

Correlated Quantum Phenomena of Spin–Orbit Coupled Perovskite Oxide Heterostructures: Cases of SrRuO3 and SrIrO3 Based Artificial Superlattices

“…Summary of reported 5d SrIrO 3 based superlattices. [75,[199][200][201][202][203][204][205][206][207][208][209][210][211][212][213][214][215][216][217][218] 5d SrIrO 3 based superlattices Functionality of partner compounds…”

“…SrIrO 3 /SrTiO 3 Quantum paraelectric [75,[199][200][201][202][203][204][205] SrIrO 3 /CaTiO 3 Incipient ferroelectric [206] SrIrO 3 /La 1-x Sr x MnO 3 (Anti-)ferromagnetic [207][208][209][210][211] SrIrO 3 /SrMnO 3 [212] SrIrO 3 /LaCoO 3 [213,214] SrIrO 3 /LaFeO 3 [215] SrIrO 3 /LaMnO 3 [216] SrIrO 3 /LaNiO 3 [217] SrIrO 3 /CaMnO 3 [218] controllability of emergent correlated behaviors. [75,[199][200][201][202][203][204][205][206][207][208][209][210][211][212][213][214][215][216][217][218] Next, we review recent exciting findings on superlattices composed of square-lattice iridates by the extensive control of lattice structure, chemical composition, etc.…”

“…Table 3 summarizes the reported SrIrO 3 based superlattices depending on the functionality of the partner perovskite oxide layer, which fosters the controllability of emergent correlated behaviors. [ 75,199–218 ] Next, we review recent exciting findings on superlattices composed of square‐lattice iridates by the extensive control of lattice structure, chemical composition, etc.…”

Hundred-Fold Enhancement in the Anomalous Hall Effect Induced by Hydrogenation

“…Excitingly, a giant enlargement of AHE loops (ρ AH - H ) is observed in Figure (see also the AHE in Figures S4 and S5 and MR in Figure S6). As shown in Figure a, the pristine SL exhibits weak (solid violet line) and unsaturated AHE loops (dashed line) associated with the interfacial ferromagnetism of SIO induced by the proximity of LCO . Surprisingly, the AHE loops undergo a significant enlargement when applying a V G of 2.7 V. Generally, ρ AH is proportional to the effective perpendicular magnetization of SIO ( M ), i.e., ρ AH = R AH · M , where R AH is the anomalous Hall coefficient .…”

“…As shown in Figure 3a, the pristine SL exhibits weak (solid violet line) and unsaturated AHE loops (dashed line) associated with the interfacial ferromagnetism of SIO induced by the proximity of LCO. 2 Surprisingly, the AHE loops undergo a significant enlargement when applying a V G of 2.7 V. Generally, ρ AH is proportional to the effective perpendicular magnetization of SIO (M), i.e., ρ AH = R AH •M, where R AH is the anomalous Hall coefficient. 1 The giant enhancement for the AHE loop thus reflects the change of magnetism of SIO as well.…”