Phonon-assisted sd electron scattering in Fe/Cr multilayers

High-resolution electrical resistivity (rho, d rho/dT) measurements are reported in a series of epitaxial Fe/Cr multilayers. In the temperature range 6-150 K we observe three distinct T-n regimes in rho(T). In the range 18 K < T < 50 K we observe n = 3, indicating the dominance of phonon-assisted interband (s/d) electron scattering. For T > 50 K, the decrease in lattice quantisation effects progressively reduces n towards 1 (classical regime), which occurs near 150 K, At lower temperatures, T less than or equal to 15 K, rho(T) exhibits a shallow anomalous minimum.