Lecture image placeholder

Premium content

Access to this content requires a subscription. You must be a premium user to view this content.

Monthly subscription - $9.99Pay per view - $4.99Access through your institutionLogin with Underline account
Need help?
Contact us
Lecture placeholder background


MMM 2022

November 07, 2022

Minneapolis, United States

Antiferromagnetically coupled CoFe/MgO/CoFe Thin Films

Exchange coupling in as-deposited and annealed magnetic trilayers Co80Fe20 (CoFe)/MgO/Co80Fe20 (CoFe) for MgO thickness spanning 0.45 to 4.5 nm has been studied. Unlike relevant existing results and theories, antiferromagnetic exchange coupling behavior was observed in annealed CoFe/MgO/CoFe with 2.7-nm MgO insulating barrier. Figure 1 shows in-plane minor hysteresis loops of the as-deposited and annealed CoFe/MgO/CoFe trilayer for MgO thickness spanning 1.8 to 4.5 nm, respectively. Interestingly, the shift of the hysteresis loop toward positive or negative field depends on the temperature. For the temperature range of 25 to 500 deg. C, the hysteresis loop is shifted to the negative and to the positive field for 600 deg. C as shown in Fig. 2(a) 1. Figure 2(b) a transition from antiferromagnetic to nearly paramagnetic response to applied magnetic field was found around 520 deg. C—conceptually called as Neel temperature. Based on grazing incidence x-ray diffraction study, formation of CoO and CoFe2O4 were found at annealed CoFe/MgO interfaces 2, which indicates they act as antiferromagnetic sources giving rise to the exchange-coupled antiferromagnetic/ferromagnetic interface and then antiferromagnetic coupling across the magnetic trilayer 3.
1 T. Ambrose et al., Phys. Rev. B 56, 83 (1997).
2 S. Grytsyuk et al., Eur. Phys. J. B. 85, 254. (2012).
3 J. Spray et al., J. Phys. D: Appl. Phys. 39, 4536 (2006).

Fig. 1 Magnetic hystereis loops of (a) as-deposited and (b) annealed CoFe/MgO/CoFe films for MgO thickness spanning 1.8 to 4.5 nm.

Fig. 2 (a) Temperature dependence of magnetic hysteresis loops of 4-nm CoFe/2.7-nm MgO/8-nm CoFe film annealed at 250 deg. C for 1 hour at the rotation angle 75 deg. (b) exchange coupling field of the same film as mentioned in (a).

Next from MMM 2022

Surface effects and spatial distribution of magnetic properties in a Kagomé artificial spin ice

Surface effects and spatial distribution of magnetic properties in a Kagomé artificial spin ice

MMM 2022

+11Agustina Asenjo
Kleber Pirota and 13 other authors

07 November 2022

Stay up to date with the latest Underline news!

Select topic of interest (you can select more than one)


  • All Lectures
  • For Librarians
  • Resource Center
  • Free Trial
Underline Science, Inc.
1216 Broadway, 2nd Floor, New York, NY 10001, USA

© 2023 Underline - All rights reserved