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G. P. Zhang

Femtosecond laser-induced demagnetization: Femtomagnetism

Department of Physics, Indiana State University, Terre Haute, IN 47809, USA
(Dated: January 10, 2019)

Magnetic materials are often manipulated with a magnetic field. However, one of the most exciting developments in magnetic materials is Femtomagnetism, where an ultrafast laser pulse can demagnetize a magnetic sample within a few hundred femtoseconds. This presents a golden opportunity for future ultrafast magnetic storage devie. In this talk, I will first give a historical account of femtomagnetism, with a short description of pioneering experimental results. I will then discuss some of our recent results in demagnetization and spin-transport, with an emphasis on on all-optical spin switching, banding mirroring, high harmonic generation and 20-fs phase transitions.

Key references:

(1) G. P. Zhang, M. S. Si, Mitsuko Murakami, Y. H. Bai and T. F. George, Generating high-order optical and spin harmonics from ferromagnetic monolayers, Nat. Comm. 9, 3031 (2018).

(2) G. P. Zhang, Y. H. Bai, T. Jenkins and T. F. George, Laser-induced ultrafast transport and demagnetization at the earliest time: First-principles and real time investigation, J. Phys.: Condensed Matter 30, 465801 (2018).

(3) G. P. Zhang, M. Murakami, M. S. Si, Y. H. Bai and T. F. George, Understanding all-optical spin switching: Comparison between experiment and theory, Modern Physics Letters B 33, 1830003 (2018).

(4) G. P. Zhang, Z. Babyak, Y. Xue, Y. H. Bai and T. F. George, First-principles and model simulation of all-optical spin reversal, Phys. Rev. B 96, 134407 (2017).