Path to scaleup technologies for cryogenic quantum computing platforms

Scaling up the number of qubits in quantum computers is essential for reaching useful quantum computing. One fundamental limitation on the number of qubits in cryogenic platforms, such as superconducting circuits and semiconductor quantum dots, is due the heat load capacity of dilution fridges and the power consumption per qubit. It was shown recently by Wallraff et al. [1] that engineering commercial cryogenic setups in terms of attenuator distributions and cabling choice can enable the support of 100 qubits. In this proposal, we present a system-level end-to-end analysis of the different technological avenues towards the scaling of commercially available cryogenic platforms for quantum computers. We overview and compare the requirements and limitations of current state of the art systems and analyze the next generation development in the field of cryogenic cabling and electronics. In such systems, we expect at least doubling  the qubit capacity of commercial dilution fridges in the near future.

[1] Krinner, Sebastian, et al. EPJ Quantum Technology 6.1 (2019).