3:45 PM - 4:00 PM
[10p-S302-9] Electrical discrimination of magnetic-skyrmion chirality via spin-orbit and -transfer torques in a branched nanowire
Keywords:magnetic skyrmion, chirality, spin-orbit torque
Recently many works on magnetic memories and logic circuits, which use a magnetic skyrmion, have been reported [1,2]. Previously we demonstrated by simulation that skyrmions with opposite chiralities of a Néel skyrmion can be formed in the same magnetic thin film, and their chiralities can be switched by introducing a single heat pulse [3]. To date the chirality has been measured by imaging a skyrmion using magnetic force microscopy (MFM) and X-ray photoemission electron microscopy [4,5]. However, to realize such a memory, an electrical method to discriminate the chiralities is essential.
In this presentation, we demonstrate an electrical method to discriminate the chirality (i.e., counter clockwise (CCW) or clockwise (CW)) of a skyrmion in a branched nanowire by using spin-orbit torque (SOT) and spin-transfer torque (STT) by using simulation [6]. The simulated results show that the motion changes depending on the chirality when additional SOT is applied on a skyrmion moving in a branched wire by STT. This method can be used as a fundamental building block for fully electrical detection in memory and logic devices using the chirality of skyrmions as a data bit in addition to the presence (and polarity) of the skyrmions as conventionally used. Our method can lead to multiple-valued operation [6].
[1] J. Iwasaki, et al. Nat. Nanotech. 8, 742-747 (2013).
[2] J. Sampaio, et al. Nat. Nanotech. 8, 839-844 (2013).
[3] Y. Nakatani, et al. Sci. Rep. 9, 13475 (2019).
[4] W. Legrand, et al. Nano Lett. 17, 2703-2712 (2017).
[5] S. Zhang, et al. Nano Lett. 18, 1057-1063 (2018).
[6] Y. Nakatani, Sci. Rep. 11, 8415 (2021).
In this presentation, we demonstrate an electrical method to discriminate the chirality (i.e., counter clockwise (CCW) or clockwise (CW)) of a skyrmion in a branched nanowire by using spin-orbit torque (SOT) and spin-transfer torque (STT) by using simulation [6]. The simulated results show that the motion changes depending on the chirality when additional SOT is applied on a skyrmion moving in a branched wire by STT. This method can be used as a fundamental building block for fully electrical detection in memory and logic devices using the chirality of skyrmions as a data bit in addition to the presence (and polarity) of the skyrmions as conventionally used. Our method can lead to multiple-valued operation [6].
[1] J. Iwasaki, et al. Nat. Nanotech. 8, 742-747 (2013).
[2] J. Sampaio, et al. Nat. Nanotech. 8, 839-844 (2013).
[3] Y. Nakatani, et al. Sci. Rep. 9, 13475 (2019).
[4] W. Legrand, et al. Nano Lett. 17, 2703-2712 (2017).
[5] S. Zhang, et al. Nano Lett. 18, 1057-1063 (2018).
[6] Y. Nakatani, Sci. Rep. 11, 8415 (2021).