Electric current induced ultrafast demagnetization

Richard Wilson (1) , Yang Yang (2) , J. Gorchon (3, 4) , Charles-Henri Lambert (4) , Sayeef Salahuddin (3, 4) , Jeffrey Bokor (3, 4)

1 UC Riverside - University of California [Riverside]
2 Department of Materials Science and Engineering [Berkeley]
3 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
4 EECS - Department of Electrical Engineering and Computer Science [Berkeley]

We report the magnetic response of Co/Pt multilayers to picosecond electrical heating. Using photoconductive Auston switches, we generate electrical pulses with 5.5 ps duration and hundreds of pico-Joules to pass through Co/Pt multilayers. The electrical pulse heats the electrons in the Co/Pt multilayers and causes an ultrafast reduction in the magnetic moment. A comparison between optical and electrically induced demagnetization of the Co/Pt multilayers reveals significantly different dynamics for optical vs electrical heating. We attribute the disparate dynamics to the dependence of the electron-phonon interaction on the average energy and the total number of initially excited electrons.

Domaines: Matière Condensée [cond-mat]

Richard Wilson, Yang Yang, J. Gorchon, Charles-Henri Lambert, Sayeef Salahuddin, et al.. Electric current induced ultrafast demagnetization. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2017, 96, ⟨10.1103/PhysRevB.96.045105⟩. ⟨hal-02388423⟩