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Current issue   Ukr. J. Phys. 2017, Vol. 62, N 5, p.441-447
https://doi.org/10.15407/ujpe62.05.0441    Paper

Chornous A.M.1, Shkurdoda Yu.O.1, Loboda V.B.1, Kolomiets V.M.2

1 Sumy State University
(2, Rimskii-Korsakov Str., Sumy 40007, Ukraine; e-mail: yu.shkurdoda@gmail.com)
2 Institute of Applied Physics, Nat. Acad. of Sci. of Ukraine
(58, Petropavlivs’ka Str., Sumy 40030, Ukraine)

Temperature Effect on Magnetoresistive Properties of Fe and Co Island Films

Section: Nanosystems
Original Author's Text:  Ukrainian/English

Abstract: Magnetoresistive properties of ultrathin Fe and Co films with effective thicknesses d = 3÷30 nm are studied in a temperature interval of (150–700) K. For films with d = 3÷10 nm, the electrical conductivity is found to be thermally activated and the tunnel magnetoresistance effect is revealed. A decrease of the temperature down to 150 K in measurements on as-condensed films is found to result in the appearance of the magnetoresistive hysteresis and a reduction of the tunnel magnetoresistance (TMR) in a thickness interval of 10–15 nm. The maximum TMR value in the fields up to 0.7 T amounted to 1% for the as-condensed Fe films with an effective thickness of 17 mm and the Fe films with an effective thickness of 8 mm annealed at a temperature of 520 K.

Key words: island film, tunnel magnetoresistance, spin-dependent tunneling, thermally induced conductivity.

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