Simulation of the heat transfer process of superconducting films in the resistive state

The heat transfer in a contact–film–substrate system was analyzed under conditions in which the heat removal from a sample to the substrate is insufficient to avoid overheating of the sample. A method for increasing the heat removal from thin-film samples is proposed for low temperatures, when a high-density electric current passes through them. The property of an anomalously high thermal conductivity of copper at temperatures from 5 to 50 K is used as the main factor of the heat-sink intensification. The heat-conduction equation for the film–substrate system is solved numerically under the condition of an additional heat transfer to the potential contacts. It is shown that beryllium bronze contacts can provide an effective heat removal from samples of superconducting films in the resistive state under the conditions of a strong Joule heat release.