Experiments on the relation between GMR and interface roughness and on the interlayer exchange coupling across semiconductors

• Published in: Journal of physics. D, Applied physics Vol. 35; no. 19; pp. 2403 - 2409
• Main Authors: Grünberg, P, Bürgler, D E, Gareev, R, Olligs, D, Buchmeier, M, Breidbach, M, Kuanr, B, Schreiber, R
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Bristol IOP Publishing 07.10.2002; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Giant magnetoresistance; Magnetic properties and materials; Magnetotransport phenomena, materials for magnetotransport; Physics; Spin waves; Semiconductor materials; Light scattering; Roughness; Ferromagnetic materials; Iron; Giant magnetoresistance; Solid-solid interfaces; Microscopic model; RHEED; Experimental study; Chromium; Electron spin interaction; Coupled modes; Silicon; Iron silicides; Exchange interactions
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/0022-3727/35/19/312

Recent experiments on 'giant magnetoresistance' (GMR) and interlayer exchange coupling are reviewed. For a quantitative analysis of the coupling the frequency spectrum of coupled spinwave modes as observable by means of Brillouin light scattering can be evaluated. In the microscopic mechanism leading to GMR the contribution of spin-dependent scattering originating from interface roughness of the ferromagnetic/non-ferromagnetic interfaces is unambiguously identified in the case of Fe/Cr structures. We focus furthermore on the question of coupling mediated by semiconducting interlayers, which we investigated in the case of Fe(1-x)Si(x) and Si interlayers. Coupling across well ordered Si interlayers turns out to be surprisingly strong, in particular considering the fact that electrical CPP resistivity is found to be large. (Author)