Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2023
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2306.05883 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911781418434560 |
|---|---|
| author | Anferov, Alexander Lee, Kan-Heng Zhao, Fang Simon, Jonathan Schuster, David I. |
| author_facet | Anferov, Alexander Lee, Kan-Heng Zhao, Fang Simon, Jonathan Schuster, David I. |
| contents | Niobium offers the benefit of increased operating temperatures and frequencies for Josephson junctions, which are the core component of superconducting devices. However existing niobium processes are limited by more complicated fabrication methods and higher losses than now-standard aluminum junctions. Combining recent trilayer fabrication advancements, methods to remove lossy dielectrics and modern superconducting qubit design, we revisit niobium trilayer junctions and fabricate all-niobium transmons using only optical lithography. We characterize devices in the microwave domain, measuring coherence times up to $62~μ$s and an average qubit quality factor above $10^5$: much closer to state-of-the-art aluminum-junction devices. We find the higher superconducting gap energy also results in reduced quasiparticle sensitivity above $0.16~$K, where aluminum junction performance deteriorates. Our junction process is readily applied to standard optical-based foundry processes, opening new avenues for direct integration and scalability, and paves the way for higher-temperature and higher-frequency quantum devices. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2306_05883 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Improved Coherence in Optically-Defined Niobium Trilayer Junction Qubits Anferov, Alexander Lee, Kan-Heng Zhao, Fang Simon, Jonathan Schuster, David I. Quantum Physics Applied Physics Niobium offers the benefit of increased operating temperatures and frequencies for Josephson junctions, which are the core component of superconducting devices. However existing niobium processes are limited by more complicated fabrication methods and higher losses than now-standard aluminum junctions. Combining recent trilayer fabrication advancements, methods to remove lossy dielectrics and modern superconducting qubit design, we revisit niobium trilayer junctions and fabricate all-niobium transmons using only optical lithography. We characterize devices in the microwave domain, measuring coherence times up to $62~μ$s and an average qubit quality factor above $10^5$: much closer to state-of-the-art aluminum-junction devices. We find the higher superconducting gap energy also results in reduced quasiparticle sensitivity above $0.16~$K, where aluminum junction performance deteriorates. Our junction process is readily applied to standard optical-based foundry processes, opening new avenues for direct integration and scalability, and paves the way for higher-temperature and higher-frequency quantum devices. |
| title | Improved Coherence in Optically-Defined Niobium Trilayer Junction Qubits |
| topic | Quantum Physics Applied Physics |
| url | https://arxiv.org/abs/2306.05883 |