Wydarzenia w wrześniu 2018:
SEMINARIUM
Oddziału Fizyki Magnetyków i Zjawisk Kooperatywnych
Dnia: 28.09.2018 roku (piątek)
o godzinie 10:00 w auli
referat pt.:
Magnetoforeza z wykorzystaniem strukturyzowanych układów
z prostopadłą anizotropią magnetyczną
wygłosi
SEMINARIUM INSTYTUTOWE
Dnia: 19.09.2018 roku (środa)
o godzinie 13:00 w auli
referat pt.:
Broadband dielectric spectroscopy (BDS) of high-permittivity,high-loss dielectrics and inhomogeneous conductors
wygłosi
Institute of Physics, Czech Academy of Sciences, Praha
SEMINARIUM INSTYTUTOWE
Dnia: 12.09.2018 roku (środa)
o godzinie 13:00 w auli
referat pt.:
Spin-orbit technologies: memory switching to THz generation
wygłosi
Department of Electrical and Computer Engineering, National University of Singapore
Current induced spin-orbit torques (SOTs) provide a new way to manipulate the magnetization. We first try to understand various spin textures. In order to probe spin textures, we utilize the bilinear magnetoelectric resistance [1], photovoltage microscopy [2] for topological insulators, and Lorentz transmission electron microscopy [3] for imaging of chiral spin textures, skyrmions in an exchange-coupled Co/Pd multilayer.
We then utilize those spin textures for magnetization switching. We find that a full sign reversal of SOTs occurs as the oxygen bonding increases in Pt/CoFeB/MgO, which evidences an interfacial SOT mechanism [4]. We show much enhanced current induced SOTs from Co/Pd multilayers [5], ferrimagnetic CoGd systems [6], a topological insulator Bi2Se3 [7,8] as well as an oxide heterostructure SrTiO3/LaAlO3[9,10], which generate strong spin currents to switch the magnetization. In order to understand detailed switching SOT switching mechanism, time resolved SOT spin dynamics is probed [11], and oscillatory SOT switching induced by field-like torques is measured [12]. We propose a field-free SOT switching scheme using one domain wall motion in an anti-notch structure [13]. Finally, we discuss the generation of THz for heavy metal/ferromagnet structures using SOTs [14,15].
1. P. He et al., Nat. Phys. 14, 495 (2018)
2. Y. Liu et al., Nat. Commun. 9, 2492 (2018)
3. S. Pollard et al., Nat. Commun. 8, 14761 (2017)
4. X. Qiu et al., Nat. Nanotechnol. 10, 333 (2015)
5. M. Jamali et al., Phys. Rev. Lett. 111, 246602 (2013)
6. R. Mishra et al., Phys. Rev. Lett. 118, 167201 (2017)
7. Y. Wang et al., Phys. Rev. Lett. 114, 257202 (2015)
8. Y. Wang et al., Nat. Commun. 8, 1364 (2017)
9. K. Narayanapillai et al., Appl. Phys. Lett. 105, 162405 (2014)
10. Y. Wang et al., Nano Lett. 17, 7659 (2017)
11. J. Yoon et al., Sci. Adv. 3, e1603099 (2017)
12. J. Lee et al., Commun. Phys. 1, 2 (2018)
13. J. Lee et al., Nano Lett. 18, 4669 (2018)
14. Y. Wu et al., Adv. Mat. 29, 1603031 (2017)
15. M. Chen et al., Adv. Opt. Mat. doi.org/10.1002/adom.201800430 (2018)