Engineering Single-Shot All-Optical Switching of Ferromagnetic Materials

Junta Igarashi; Quentin Remy; Satoshi Iihama; Grégory Malinowski; Michel Hehn; Jon Gorchon; Julius Hohlfeld; Shunsuke Fukami; Hideo Ohno; Stéphane Mangin

doi:10.1021/acs.nanolett.0c03373

Engineering Single-Shot All-Optical Switching of Ferromagnetic Materials

Nano Lett. 2020 Dec 9;20(12):8654-8660. doi: 10.1021/acs.nanolett.0c03373. Epub 2020 Nov 23.

Authors

Junta Igarashi^{1

2}, Quentin Remy², Satoshi Iihama^{3

4}, Grégory Malinowski², Michel Hehn², Jon Gorchon², Julius Hohlfeld², Shunsuke Fukami^{1

5

6

4

7}, Hideo Ohno^{1

5

6

4

7}, Stéphane Mangin²

Affiliations

¹ Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan.
² Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France.
³ Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 6-3 Aramaki Aza Aoba, Sendai 980-8578, Japan.
⁴ Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan.
⁵ WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan.
⁶ Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan.
⁷ Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Sendai 980-0845, Japan.

PMID: 33226825
DOI: 10.1021/acs.nanolett.0c03373

Abstract

Since it was recently demonstrated in a spin-valve structure, magnetization reversal of a ferromagnetic layer using a single ultrashort optical pulse has attracted attention for future ultrafast and energy-efficient magnetic storage or memory devices. However, the mechanism and the role of the magnetic properties of the ferromagnet as well as the time scale of the magnetization switching are not understood. Here, we investigate single-shot all-optical magnetization switching in a GdFeCo/Cu/[Co_xNi_1-x/Pt] spin-valve structure. We demonstrate that the threshold fluence for switching both the GdFeCo and the ferromagnetic layer depends on the laser pulse duration and the thickness and the Curie temperature of the ferromagnetic layer. We are able to explain most of the experimental results using a phenomenological model. This work provides a way to engineer ferromagnetic materials for energy efficient single-shot all-optical magnetization switching.

Keywords: All-optical switching; single-shot all-optical switching; spin current; spin valve; ultrafast demagnetization; ultrafast laser.