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arXiv · 1703.06756

Role of Spin Flips versus Spin Transport in Non Thermal Electrons Excited by Ultrashort Optical Pulses in Transition Metals

V. Shokeen·M. Sanchez Piaia·J. -Y. Bigot·T. Mueller·P. Elliott·J. K. Dewhurst·S. Sharma·E. K. U. Gross
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Abstract

A joint theoretical and experimental investigation is performed to understand the underlying physics of laser-induced demagnetization in Ni and Co films. Experimentally dynamics of spins is studied by determining the time-dependent amplitude of the Voigt vector and theoretically ab-initio calculations are performed using time-dependent density functional theory. We demonstrate that overall spin-orbit induced spin-flips are the most significant contributors with super-diffusive spin transport playing very limited to no role. Our study highlights the material dependent nature of the demagnetization during the process of thermalization of non-equilibrium spins.

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V. Shokeen, M. Sanchez Piaia, J. -Y. Bigot, T. Mueller, P. Elliott, J. K. Dewhurst, S. Sharma, E. K. U. Gross. 2017-03-13. Role of Spin Flips versus Spin Transport in Non Thermal Electrons Excited by Ultrashort Optical Pulses in Transition Metals. https://doi.org/10.1103/physrevlett.119.107203

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