Univ. Paris-Saclay

Service de Physique de l'Etat Condensé

Ultrafast spin dynamics: How to generate and use hot electrons to manipulate magnetization
Institut Jean Lamour, UMR CNRS 7198 – Université de Lorraine – Nancy, France
Mercredi 12/10/2022, 11:00-12:00
SPEC Salle Itzykson, Bât.774, Orme des Merisiers

Understanding and controlling the magnetization dynamics on the femtosecond timescale is becoming essential both at the fundamental level and to develop future technological applications. While direct laser excitation of a ferromagnetic layer was commonly used during the past twenty years, laser induced hot-electrons femtosecond pulses and subsequent transport in magnetic multilayers has recently attracted a lot of attention. Indeed, replacing photons by hot-electrons offers complementary information to improve our understanding of ultrafast magnetization dynamics and to provide new possibilities for manipulating the magnetization in a thin magnetic heterostructure on the femtosecond timescale.
In this talk, I will focus on the generation and transport of hot-electrons following femtosecond laser pulse excitation. I will discuss their role in the ultrafast loss of magnetization in magnetic multilayers. I will show that hot electrons can induce an ultrafast magnetization reversal in ferrimagnetic GdFeCo alloy. Moreover, these ultrafast currents can be spin-polarized, allowing for sub-ps all-optical control of magnetization in magnetic multilayers.


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