Wiring-Efficient XYZ Line for 3D-Integrated Superconducting Devices

Scaling superconducting quantum devices is limited by the number of control lines that can be routed from room-temperature electronics to the chip inside the cryostat. Previous control multiplexing approaches combined magnetic flux and microwave controls into an XYZ line at the cryostat’s base stage [1], but still required two signal lines per qubit due to differing attenuation configurations. To address this, we introduce an XYZ line with an on-chip low-pass Chebyshev filter, whereby the qubit drive is carried out within the stopband of the filter. This allows qubit control using a single cryostat line with a single attenuation configuration. We present low- and high-frequency qubit control and discuss the fidelity of single- and two-qubit operations. Our work alleviates cryogenic wiring constraints, facilitating further scaling of superconducting quantum devices.

 

[1] R. Manenti et al., Appl. Phys. Lett. 119, 14 (2021)