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arXiv · 2004.09822

Ultrafast antiferromagnetic switching in NiO induced by spin transfer torques

Théophile Chirac·Jean-Yves Chauleau·Pascal Thibaudeau·Olena Gomonay·Michel Viret
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Abstract

NiO is a prototypical antiferromagnet with a characteristic resonance frequency in the THz range. From atomistic spin dynamics simulations that take into account the crystallographic structure of NiO, and in particular a magnetic anisotropy respecting its symmetry, we describe antiferromagnetic switching at THz frequency by a spin transfer torque mechanism. Sub-picosecond S-state switching between the six allowed stable spin directions is found for reasonably achievable spin currents, like those generated by laser induced ultrafast demagnetization. A simple procedure for picosecond writing of a six-state memory is described, thus opening the possibility to speed up current logic of electronic devices by several orders of magnitude.

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Théophile Chirac, Jean-Yves Chauleau, Pascal Thibaudeau, Olena Gomonay, Michel Viret. 2020-04-21. Ultrafast antiferromagnetic switching in NiO induced by spin transfer torques. https://doi.org/10.1103/physrevb.102.134415

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