Exploring the quantum transport properties of superconductor-constriction-superconductor type devices based on platinum silicide (PtSi)*

Transition metal (TM) silicides are extensively used in semiconductor microelectronic devices due to their ability to establish low-resistance connections with silicon and, in specific instances, to form coherent epitaxial interfaces. Many TM silicides, including CoSi₂, PtSi, and V₃Si, exhibit superconducting properties, making them potentially pivotal materials for integrating quantum computation with silicon technology.

With this perspective in mind, our current endeavor centers on exploring the attributes of superconducting devices fabricated by constricting the dimensions of the devices using superconducting PtSi. To achieve this, we synthesize PtSi thin films on silicon substrates and employ a single-step electron beam lithography process, followed by reactive ion etching techniques. We will discuss the initial findings from these devices, including Josephson junctions (JJs) constructed with single constrictions and Superconducting Quantum Interference Devices (SQUIDs) constructed with double constrictions. The parameters extracted from the low temperature transport measurements, including critical temperature, coherence length, critical current density, and critical field values, will be discussed in this work.

Zhang. et al. Thin-film synthesis of superconductor-on-insulator A15 vanadium silicide. Sci Rep 11, 2358 (2021).

M. Liu and C. T. Black, “Performance analysis of superconductor-constriction-superconductor transmon qubits,” (2023), arXiv:2301.04276