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arXiv · 2409.01615

All-optical helicity-dependent switching in NiCo$_2$O$_4$ thin films

Ryunosuke Takahashi·Yann Le Guen·Suguru Nakata·Junta Igarashi·Julius Hohlfeld·Grégory Malinowski·Xie Lingling·Kan Daisuke·Yuichi Shimakawa·Stéphane Mangin·Hiroki Wadati
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Abstract

All-optical switching (AOS) involves manipulating magnetization using only pulsed laser, presenting a promising approach for next-generation magnetic recording devices. NiCo2O4 (NCO) thin films, a rare-earth-free ferrimagnetic oxide, exhibit a high Curie temperature and strong perpendicular magnetic anisotropy. This study demonstrates AOS in NCO thin films at room temperature using long-duration laser pulses and high repetition rates. Unlike previous findings, the AOS phenomena we report here are helicity-dependent and observable with an ultrashort pulsed laser. Consequently, two distinct types of AOS can be observed in a single NCO thin film, contingent on the characteristics of the laser pulses and temperature.

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Ryunosuke Takahashi, Yann Le Guen, Suguru Nakata, Junta Igarashi, Julius Hohlfeld, Grégory Malinowski, Xie Lingling, Kan Daisuke, Yuichi Shimakawa, Stéphane Mangin, Hiroki Wadati. 2024-09-03. All-optical helicity-dependent switching in NiCo$_2$O$_4$ thin films. https://doi.org/10.1063/5.0253785

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