Influence of absorbent layer on nonlinear microwave properties of HTS-based coplanar waveguide

The paper presents the results of continuing experimental studies of a coplanar waveguide on the basis of YBCO thin film (75 nm) depending on the input power and DC level. It is shown that use of a highly absorbent material on the back side of the substrate changes HTS transition characteristics in a strongly dissipative state. Apparently it is caused by a changing in the heat transfer between the structure and the helium gas filling the structure chamber. This fact leads to a decreasing the value of DC corresponding to a structure transition to a highly dissipative state.