Center for Correlated Electron Systems


Emergent Magnetic Order in Sr2IrO4/Ca3Ru2O7 Heterostructures

November 29, 2022l Hit 76
Date : September 30, 2022 13:30 ~ 15:00
Speaker : Prof. Ambrose Seo (University of Kentucky)
Location : Bldg. 19, Rm. 210

I will discuss the observation of a new interlayer antiferromagnetic stacking order in Sr2IrO4/Ca3Ru2O7 heterostructures, where substantially large orthorhombic distortion (> 1.5%) is applied to the Sr2IrO4 thin film. The orthorhombic distortion lowers the crystal symmetry of Sr2IrO4 from tetragonal to orthorhombic, evoking competition between interlayer exchange and pseudo-dipolar interactions. Using resonant X-ray magnetic scattering, we observed La2CuO4-like interlayer antiferromagnetic order where the magnetic moment is parallel to the elongated b-axis and its stacking pattern is inverted from that of the tetragonal Sr2IrO4 crystal. This interlayer stacking order emerges since the nearest interlayer exchange interaction exceeds the interlayer pseudo-dipolar interaction. Our result suggests a new knob for tuning the long-range magnetic order and enhancing the magnetic quantum fluctuations in quasi-two-dimensional systems.


Host : Prof. Tae Won Noh