Localization of conduction electrons in the ferromagnetic clusters AuFe

• Published in: JETP letters Vol. 89; no. 9; pp. 466 - 470
• Main Authors: Prokhorov, A. S., Zhukova, E. S., Gorshunov, B. P., Hesselberth, M. B. S., Aarts, J., Nieuwenhuys, G. J., Kaiser, S., Dressel, M.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01.07.2009
• Subjects: Atomic; Biological and Medical Physics; Biophysics; Condensed Matter; Molecular; Optical and Plasma Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Quantum Information Technology; Solid State Physics; Spintronics; 78.30.Er; 78.66.-w; 75.50.Lk
• ISSN: 0021-3640; 1090-6487
• DOI: 10.1134/S0021364009090094

The optical-conductivity spectra of concentrated solutions Au 1 − x Fe x with x = 17 and 22 at % have been measured in a frequency range of (10–33) × 10 3 cm −1 at room temperature. The results are analyzed together with previous optical data obtained for compounds with x = 4–12 at %. It is found that the magnetic contributions σ magn = σ AuFe − σ Au to dc and low-frequency(10 cm −1 ) conductivities for an Fe concentration below 4 at % are almost equal, while the low-frequency magnetic contribution for larger concentrations is significantly larger than the dc one. An absorption band at frequencies of 1000–3000 cm −1 has been found for samples with concentrations x = 6–22 at %. The observed phenomena are attributed to the localization of electrons inside clusters containing ferromagnetically ordered iron ions.