Anomalous Features in Surface Impedance of Y-Ba-Cu-O Thin Films: Dependence on Frequency, RF and DC Fields

Anton V. Velichko, Adrian Porch, Richard G. Humphreys

Two high-quality Y-Ba-Cu-O thin films on MgO substrates have been investigated using the coplanar resonator technique at 8 and 16 GHz. Both films exhibit an anomalous decrease in t…