Low thermal conductivity superconducting metallized Mylar leads

We describe the fabrication of PbSn-coated, 2.5-μm-thick, Mylar ribbons that can be used as electrical leads in low-temperature experiments. We present measurements of the thermal conductivity of the leads and of uncoated Mylar ribbons between 0.08 and 2.0 K. At 0.1 K, a conveniently sized coated Mylar lead has the same thermal conductance as an approx.6-μm-diam manganin wire of the same length