Liquid metal printing for superconducting circuits

Superconducting circuits are a promising platform for the implementation of fault-tolerant quantum computers, quantum limited amplifiers, ultra-low power electronics and sensors with ultimate sensitivity. Its success is in part due to the possibility to implement circuit designs with industry-standard planar lithography, generally associated with a high level of control over defects and contaminants. Additive approaches to circuit fabrication are an alternative, but are usually expected to be inferior in this respect. Here we show that liquid-metal based micro-pipette printing can be used to fabricate superconducting lumped-element resonators with state-of-the-art coherence times. This demonstrates the technique's suitability for use in the fabrication of low-loss superconducting devices.