DQMP Informal Seminar - Electrical control of spin-orbit coupling for novel spintronics applications - Min-Gu Kang
12.02.2025 14:00 – 15:30
Electrical control of spin-orbit coupling for novel spintronics applications
Min-Gu Kang, ETH Zurich
Spin-orbit coupling effect in structures with broken inversion symmetry, known as the Rashba effect, facilitates spin-orbit torques (SOTs) in heavy metal (HM)/ferromagnet (FM)/oxide structures, along with the spin Hall effect. However, conventional HM/FM/oxide structures impose a symmetry constraint of the spin-orbit coupling effect, reflecting the spin current polarization in orthogonal directions. This talk introduces two novel approaches to overcome these limitations: lateral symmetry modulation via asymmetric gate voltages [1,2], and the incorporation of chirality-induced spin selectivity (CISS) effect into spin valve [3]. Lateral modulation of Rashba effect in Pt/Co/AlOx structures generates out-of-plane SOTs, enabling field-free perpendicular magnetization switching and electrical polarity control. The second part focuses on room temperature magnetoresistance (MR) in a chiral spin valve comprising chiral perovskites/AlOx/perpendicular ferromagnet structures. Chiral MR increases with rising temperatures, suggesting that phonon-induced enhancement of spin-orbit coupling plays a critical role in CISS effect in our device. Additionally, introducing chiral molecules with amplified chirality enhances the MR effect.
[1]M.-G. Kang et al. Electric-field control of field-free spin-orbit torque switching via laterally modulated Rashba effect in Pt/Co/AlOx structures, Nat. Commun. 12, 7111 (2021)
[2]J. Jeong et al. Nanosecond magneto-ionic control of interfacial magnetism using a resistive switching in HfO2 gate oxide, Adv. Electron. Mater. 2400535 (2024)
[3]M.-G. Kang et al. Room temperature chiral magnetoresistance in a chiral-perovskites-based perpendicular spin valve, APL Mater. 12, 081118 (2024)
Lieu
Bâtiment: Ecole de Physique
Salle MaNEP
Organisé par
Département de physique de la matière quantiqueIntervenant-e-s
Min-Gu Kang , ETH Zurichentrée libre