0468974 - FZÚ 2017 RIV US eng J - Článek v odborném periodiku
Stupakov, Alexandr - Bagdinov, A.V. - Prokhorov, V.V. - Bagdinova, A.N. - Demikhov, E.I. - Dejneka, Alexandr - Kugel, K.I. - Gorbatsevich, A.A. - Pudonin, F.A. - Kovaleva, Natalia
Out-of-plane and in-plane magnetization behavior of dipolar interacting FeNi nanoislands around the percolation threshold.
Journal of Nanomaterials. Roč. 2016, Oct (2016), s. 1-9, č. článku 3190260. ISSN 1687-4110. E-ISSN 1687-4129
Grant CEP: GA ČR GA15-13778S
Institucionální podpora: RVO:68378271
Klíčová slova: FeNi nanoisland * nanomagnetism
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 1.871, rok: 2016 ; AIS: 0.486, rok: 2016
DOI: https://doi.org/10.1155/2016/3190260

Magnetic properties of inhomogeneous nanoisland FeNi films were studied by SQUID magnetometry. The FeNi films with nominal thickness ranging from 0.6 to 2.0 nm were deposited by rf sputtering on Sitall glass substrates and covered by a protecting Al2O3 layer on the top. The SQUID data indicate pronounced irreversibility behavior for the out-of-plane temperature-dependent magnetization response (measured at H ≃ 100 Oe) using zero-field cooling (ZFC) and field-cooled warming (FCW) after the applied dc magnetizing field H m ≃ 2 T for the FeNi samples with nominal thickness 1.1 nm ≲ d ≲ 1.8 nm, below the percolation threshold. The positive difference between the FCW and ZFC data identifies two irreversibility temperature scales, T B ≈ 50 K and T ≈ 200 K, which can be associated with the superparamagnetic and superferromagnetic behavior in inhomogeneous nanoisland FeNi films, respectively. However, above the film percolation threshold, we observed a crossover from the out-of-plane to in-plane magnetization orientation. Here, the in-plane FCW-ZFC difference implies negative remanent magnetization response in the temperature range T B ≲ T ≲ T . The observed magnetization properties can be associated with the presence of the superferromagnetic phase in self-assembled clusters of quasi-2D metallic magnetic FeNi nanoislands.
Trvalý link: http://hdl.handle.net/11104/0266928