Picosecond Switching of Optomagnetic Tunnel Junctions

Luding Wang; Houyi Cheng; Pingzhi Li; Yang Liu; Youri L. W. van Hees; Reinoud Lavrijsen; Xiaoyang Lin; Kaihua Cao; Bert Koopmans; Weisheng Zhao

doi:10.1073/pnas.2204732119

arXiv · 2011.03612

Picosecond Switching of Optomagnetic Tunnel Junctions

Luding Wang·Houyi Cheng·Pingzhi Li·Yang Liu·Youri L. W. van Hees·Reinoud Lavrijsen·Xiaoyang Lin·Kaihua Cao·Bert Koopmans·Weisheng Zhao

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Abstract

Perpendicular magnetic tunnel junctions are one of the building blocks for spintronic memories, which allow fast nonvolatile data access, offering substantial potentials to revolutionize the mainstream computing architecture. However, conventional switching mechanisms of such devices are fundamentally hindered by spin polarized currents4, either spin transfer torque or spin orbit torque with spin precession time limitation and excessive power dissipation. These physical constraints significantly stimulate the advancement of modern spintronics. Here, we report an optomagnetic tunnel junction using a spintronic-photonic combination. This composite device incorporates an all-optically switchable Co/Gd bilayer coupled to a CoFeB/MgO-based perpendicular magnetic tunnel junction by the Ruderman-Kittel-Kasuya-Yosida interaction. A picosecond all-optical operation of the optomagnetic tunnel junction is explicitly confirmed by time-resolved measurements. Moreover, the device shows a considerable tunnel magnetoresistance and thermal stability. This proof-of-concept device represents an essential step towards ultrafast spintronic memories with THz data access, as well as ultralow power consumption.

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Luding Wang, Houyi Cheng, Pingzhi Li, Yang Liu, Youri L. W. van Hees, Reinoud Lavrijsen, Xiaoyang Lin, Kaihua Cao, Bert Koopmans, Weisheng Zhao. 2020-11-06. Picosecond Switching of Optomagnetic Tunnel Junctions. https://doi.org/10.1073/pnas.2204732119

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