Influence of substrate-induced strain on exchange bias effect in YSMO/LSMO heterostructures

Magnetic properties of Y0.67Sr0.33MnO3 (YSMO) and La0.67Sr0.33MnO3 (LSMO) thin films heterostructures (YSMO/LSMO) deposited on single-crystalline (001) SrTiO3 (STO), (001) LaAlO3 (LAO) and MgO substrates using pulsed laser deposition technique were investigated. Magnetization (M) vs. the applied field (H) measurements revealed shift in hysteresis loop showing the exchange bias effect of about 80 Oe for the heterostructures on LAO substrate, which was absent for those on STO substrates. In order to investigate this, single-layer LSMO layers were deposited on these substrates. X-ray diffraction patterns revealed significant compressive strain and a weaker tensile strain for LSMO films on LAO and STO substrates, respectively. Raman spectroscopy measurements further confirmed the lattice mismatch-induced strain in LSMO layer on LAO substrate. These different strain conditions in LSMO films on both the substrates are suggested to be contributing to the emergence of different magnetic ground states in these systems, which could be leading to pinning of spins at the interface and resulting in a significant exchange bias effect (EBE) on LAO substrate.

Automated summary

Magnetic properties of Y0.67Sr0.33MnO3 (YSMO) and La0.67Sr0.33MnO3 (LSMO) thin films heterostructures (YSMO/LSMO) on different substrates were investigated. The results showed that the heterostructures on LAO substrate exhibited an exchange bias effect of about 80 Oe, while those on STO substrates did not. The different strain conditions in LSMO films on LAO and STO substrates are suggested to contribute to the emergence of different magnetic ground states, leading to the significant exchange bias effect on LAO substrate.