52nd CEMS Colloquium

Title

Voltage control of magnetic anisotropy, exchange interaction and DMI in MgO / 3d ferromagnetic thin film system

Abstract

In this talk, I report recent progresses in voltage control of magnetism at room temperature in all solid state devices with 3d transition metal ferromagnetic thin films. Magnetic anisotropy control using electric-field at room temperature in all solid-state devices was first done using an Fe ultrathin film grown on Au(001) surface and covered by an MgO layer [1]. The effect was soon applied to switch magnetization coherently [2], to excite ferromagnetic resonance (FMR) [3], and to modulate spin waves and DMI [4]. Recently, voltage modulation of the exchange constant is also demonstrated [5-7]. In my talk those progresses in voltage control and a progress in understanding the mechanism based on a XMCD study [8] will be presented.

Acknowledgements:
The work was partly supported by ImPACT program of Japanese Cabinet, and Bilateral (Japan-Vietnam) collaboration program of JSPS (17038811-000084). The work has been carried out by collaboration between AIST, Japan, SPring-8, NIMS, Tohoku University and Osaka University. I acknowledge to S. Miwa, K. Tanaka, K. Matsuda, F. Bonell, K. Nawaoka, T. V. Pham of Osaka University, T. Nozaki, Y. Shiota, W. Skowronski, K. Yakushiji, L. D. Duong, H. Kubota, A. Fukushima, S. Yuasa of AIST, M. Tsujikawa, M. Shirai of Tohoku University, T. Ohkubo, K. Hono of NIMS and M. Suzuki, Y. Kotani, T. Nakamura of Spring-8 for their collaborations.

References:
[1] Maruyama, T. et al., Nature Nanotech. 4, 158-161 (2009).
[2] Shiota, Y. et al., Nature Materials, 11, 39-43 (2012).
[3] Nozaki, T. et al., Nature Phys. 8, 491 (2012).
[4] Nawaoka, K. et al., Appl. Phys. Express 8, 063004 (2015).
[5] Ando, F. et al., Appl. Phys. Lett., 109, 022401 (2016).
[6] T. Dohi, et al., AIP Advances 6, 075017 (2016).
[7] J. Cho, private communication.
[8] Miwa, S. at al., Nature Communication, in press.