%0 Journal Article
%K Superconducting films
%K Magnetoresistance
%K Perovskite
%K Manganese
%K High temperature superconductors
%K Magnetic properties
%K Electric conductivity of solids
%K Magnetic variables measurement
%K Direct current resistivity
%K Surface resistances
%A S.E Lofland
%A M Dominguez
%A S.D Tyagi
%A S.M Bhagat
%A M.C Robson
%A C Kwon
%A Z Trajanovic
%A I Takeuchi
%A Ramamoorthy Ramesh
%A T Venkatesan
%B Thin Solid Films
%D 1996
%G eng
%P 256-261
%T Surface resistance of thin Perovskite films - High-temperature superconductors and giant magnetoresistance manganites
%V 288
%X We present a systematic study of the surface resistance of perovskite thin films and bulk samples at microwave frequencies. The d.c. resistivity p of the various samples spans three orders of magnitude. For bulk samples, we obtain the usual ρ1/2 dependence of Rs. For ρ < 1 μΩ cm, Rs displays conventional behavior, i.e. Rs α ρ. However, for ρ > 1 μΩ cm, Rs is not proportional to ρ but to the conductivity σ. Using this fact, we have made the first direct observation of a peak in σ1, just below Tc in a-axis films of YBa2Cu3O7.