Ultrafast control of magnetic interactions by optical pulses
We succeeded in optically controlling magnetic interactions in ferromagnetic semiconductor EuO thin films doped with Gd ions. When the Gd concentration is low, the magnetic interaction increases by ultrashort laser pulses, whereas it decreases when the Gd concentration is high. In ferromagnetic Eu1-xGdxO, we thereby demonstrate the strengthening as well as the weakening of the magnetic order by 10% and within 3 ps by optically controlling the magnetic exchange interaction. This principle - ultrafast optical control of magnetic interaction - can be applied to future ultrafast opto-spintronics.
- 1 Department of Physics, Tohoku University