Photoinduced transient states of antiferromagnetic orderings in La_1/3Sr_2/3FeO₃ and SrFeO_3−δ thin films observed through time-resolved resonant soft x-ray scattering

Abstract

The relationship between the magnetic interaction and photoinduced dynamics in antiferromagnetic perovskites is investigated in this study. In La1/3Sr2/3FeO3 thin films, commensurate spin ordering is accompanied by charge disproportionation, whereas SrFeO3−δ thin films show incommensurate helical antiferromagnetic spin ordering due to increased ferromagnetic coupling compared to La1/3Sr2/3FeO3. To understand the photoinduced spin dynamics in these materials, we investigate the spin ordering through time-resolved resonant soft x-ray scattering. In La1/3Sr2/3FeO3, ultrafast quenching of the magnetic ordering within 130 fs through a nonthermal process is observed, triggered by charge transfer between the Fe atoms. We compare this to the photoinduced dynamics of the helical magnetic ordering of SrFeO3−δ . We find that the change in the magnetic coupling through optically induced charge transfer can offer an even more efficient channel for spin-order manipulation.