Title: Oral: Tuning Electrical Properties in YBCO Films Using Direct-Write Cobalt Ion Implantation

In this work, we explore cobalt ion implantation into YBCO thin films as part of a study on direct-write patterning using a liquid metal alloy ion source. Cobalt was chosen due to its compatibility with YBCO. Cobalt ions (40 keV) were implanted into patterned electrodes at fluences ranging from 1 × 10¹³ to 3 × 10¹⁴ ions/cm², and we report the temperature dependence of resistivity and the residual resistivity in the implanted regions. At the highest fluence, we observed a five-order-of-magnitude increase in resistivity compared to the unirradiated film, a change significantly higher than typically observed with inert gas ion implantations. This work demonstrates the feasibility of high-throughput, direct-write lithography for patterning YBCO films, offering a viable alternative to conventional photolithography and argon ion etching.