Materials challenges and opportunities for quantum computing hardware

NP De Leon, KM Itoh, D Kim, KK Mehta, TE Northup… - Science, 2021 - science.org
BACKGROUND The past two decades have seen intense efforts aimed at building quantum
computing hardware with the potential to solve problems that are intractable on classical …

Towards understanding two-level-systems in amorphous solids: insights from quantum circuits

C Müller, JH Cole, J Lisenfeld - Reports on Progress in Physics, 2019 - iopscience.iop.org
Amorphous solids show surprisingly universal behaviour at low temperatures. The
prevailing wisdom is that this can be explained by the existence of two-state defects within …

[HTML][HTML] A quantum engineer's guide to superconducting qubits

P Krantz, M Kjaergaard, F Yan, TP Orlando… - Applied physics …, 2019 - pubs.aip.org
The aim of this review is to provide quantum engineers with an introductory guide to the
central concepts and challenges in the rapidly accelerating field of superconducting …

Surpassing millisecond coherence in on chip superconducting quantum memories by optimizing materials and circuit design

S Ganjam, Y Wang, Y Lu, A Banerjee, CU Lei… - Nature …, 2024 - nature.com
The performance of superconducting quantum circuits for quantum computing has advanced
tremendously in recent decades; however, a comprehensive understanding of relaxation …

Materials loss measurements using superconducting microwave resonators

CRH McRae, H Wang, J Gao, MR Vissers… - Review of Scientific …, 2020 - pubs.aip.org
The performance of superconducting circuits for quantum computing is limited by materials
losses. In particular, coherence times are typically bounded by two-level system (TLS) …

Moving beyond the transmon: Noise-protected superconducting quantum circuits

A Gyenis, A Di Paolo, J Koch, A Blais, AA Houck… - PRX Quantum, 2021 - APS
Artificial atoms realized by superconducting circuits offer unique opportunities to store and
process quantum information with high fidelity. Among them, implementations of circuits that …

Disentangling losses in tantalum superconducting circuits

KD Crowley, RA McLellan, A Dutta, N Shumiya… - Physical Review X, 2023 - APS
Superconducting qubits are a leading system for realizing large-scale quantum processors,
but overall gate fidelities suffer from coherence times limited by microwave dielectric loss …

Semiconductor-nanowire-based superconducting qubit

TW Larsen, KD Petersson, F Kuemmeth, TS Jespersen… - Physical review …, 2015 - APS
We introduce a hybrid qubit based on a semiconductor nanowire with an epitaxially grown
superconductor layer. Josephson energy of the transmonlike device (“gatemon”) is …

Reducing intrinsic loss in superconducting resonators by surface treatment and deep etching of silicon substrates

A Bruno, G De Lange, S Asaad… - Applied Physics …, 2015 - pubs.aip.org
We present microwave-frequency NbTiN resonators on silicon, systematically achieving
internal quality factors above 1 M in the quantum regime. We use two techniques to reduce …

Loss mechanisms in superconducting thin film microwave resonators

J Goetz, F Deppe, M Haeberlein, F Wulschner… - Journal of Applied …, 2016 - pubs.aip.org
We present a systematic analysis of the internal losses of superconducting coplanar
waveguide microwave resonators based on niobium thin films on silicon substrates. In …