EXCIMER LASER TREATED Ag/Go MULTILAYERS EXHIBITING GMR EFFECT
M.Jergel,a A. Anopcenko,a E.Majková,a M.Spasova,a S.Lubya, V.Holy,b M.Brunel,c A.Luches,d and M.Martinod
aInstitute of Physics of the Slovak Academy of Sciences,Dúbravská cesta 9,84228 Bratislava,Slovakia
b
Laboratory of Thin Films and Nanostructures,Masaryk University,Kotlárská 2,611 37 Brno, Czech Republicc
Laboratoire de Cristallographie du CNRS,B.P.166 38042 Grenoble,Franced
I.N.F.M.and University of Lecce,Department of Physics, 73100 Lecce,ItalyIn interplay between the structure and giant magnetoresistance is studied on three Agx-Coy multilayers of different layer thickness ratios x/y exposed to (1-200) shots of excimer XeCl laser pulses with the fluences of (0.1-0.25) Jcm-2. Below melting threshold, a strong texture present in Ag4-Co1 stabilizes the GMR value while random polycrystalline structure in Ag6-Co1 enables to improve the GMR systematically. In Ag2-Co1, the temperature window for grain-boundary diffusion is too narrow to effect the GMR in a reasonable way. When the Ag melting threshold is reached, rapid solidification produces a granular-like structure irrespective of the structural character of the original multilayer and the GMR value changes unpredictably in a broad interval.