Exchange Spring in a Heterostructure with Pd0.96Fe0.04 Low-Temperature Ferromagnet

• Published in: Technical physics letters Vol. 45; no. 4; pp. 379 - 382
• Main Authors: Yanilkin, I. V., Mukhametova, E. T., Vakhitov, I. R., Gumarov, A. I., Yusupov, R. V., Tagirov, L. R.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.04.2019; Springer Nature B.V
• Subjects: Aluminum oxide; Anisotropy; Antiferromagnetism; Classical and Continuum Physics; Cobalt; Exchanging; Ferromagnetism; Heterostructures; Hysteresis loops; Low temperature; Magnetic moments; Magnetron sputtering; Molecular beam epitaxy; Physics; Physics and Astronomy; Sapphire; Single crystals; Thin films
• ISSN: 1063-7850; 1090-6533
• DOI: 10.1134/S1063785019040321

The exchange bias of the magnetic hysteresis loop and the exchange-spring effect have been observed in thin-film heterostructures comprising layers of Pd 0.96 Fe 0.04 low-temperature ferromagnet, metallic cobalt, and cobalt monoxide (CoO) grown on single-crystalline sapphire by methods of magnetron sputtering and molecular beam epitaxy in an ultrahigh-vacuum system. It is established that the exchange anisotropy of Pd 0.96 Fe 0.04 layer in Pd 0.96 Fe 0.04 /CoO/Co/Al 2 O 3 thin-film heterostructure is absent and the exchange-spring effect in this system is not manifested. In the case of a Pd 0.96 Fe 0.04 /Co/CoO/Al 2 O 3 structure, it is shown that, according to the results of magnetometric measurements, the inversion of the order of antiferromagnetic and ferromagnetic layers leads to pinning of the magnetic moment of Pd 0.96 Fe 0.04 layer at the interface with cobalt and to realization of the exchange-spring effect. Additional evidence in favor of this interpretation was obtained using the micromagnetic modeling of magnetic hysteresis loops.