--> Quantum Physics arXiv:2605.30425 (quant-ph) [Submitted on 28 May 2026] Title:Dually tunable YBCO coplanar waveguide resonators based on helium-ion-generated Josephson inductances Authors:Kenny Fohmann, Timo J. Glebe-Märklin, Benedikt Wilde, Mohamad Kazouini, Christoph Schmid, Dieter Koelle, Reinhold Kleiner, Daniel Bothner View a PDF of the paper titled Dually tunable YBCO coplanar waveguide resonators based on helium-ion-generated Josephson inductances, by Kenny Fohmann and 7 other authors View PDF Abstract:Superconducting microwave circuits with and without Josephson inductances are the Swiss Army knife for many experiments and technologies from quantum information science to astrophysical particle detectors. Despite a large variety of existing circuit types, thin film materials and Josephson junction technologies, a flexible and reliable platform for high-magnetic-field and high-temperature applications is yet to be found. In this manuscript, we investigate coplanar waveguide cavities made of the high-temperature cuprate superconductor YBa$_2$Cu$_3$O$_7$ (YBCO), integrated with Josephson inductances and quantum interferometers that are generated by the controlled local irradiation of the YBCO with a focused helium ion beam. We obtain strongly flux-tunable microwave resonators, which not only display periodic interferometer oscillations of resonance frequency and decay rate, but also a superimposed Fraunhofer-like modulation pattern. The latter originates from the magnetic field tuning of the individual Josephson junction critical currents due to the out-of-plane junction barriers. It allows adjusting resonance frequency and flux responsivity independently of each other, potentially enabling tunable microwave circuits with low sensitivity to external magnetic-field noise over a broad range of frequencies. Finally, we investigate the temperature dependence of the cavities, show that they have promising characteristics up to 14$\,$K, and present a model for the 

Google

NASA

arXiv Quantum Physics

Dually tunable YBCO coplanar waveguide resonators based on helium-ion-generated Josephson inductances

dually-tunable-ybco-coplanar-waveguide-resonators-based-helium-ion-generated

--> Quantum Physics arXiv:2605.30426 (quant-ph) [Submitted on 28 May 2026] Title:Detecting bipartite entanglement with PnCP maps and non-negative polynomials Authors:Gaël Massé, Mounir Rezig, Paul Catala, Santiago Scheiner, Laia Serradesanferm Córdoba, Enky Oudot, Damian Markham View a PDF of the paper titled Detecting bipartite entanglement with PnCP maps and non-negative polynomials, by Ga\"el Mass\'e and 5 other authors View PDF HTML (experimental) Abstract:Positive non-Completely Positive (PnCP) maps are an essential tool to detect entanglement since their characterization is a dual aspect of the separability problem. A recent algorithm proposed by Kelp et al. explains how to generate PnCP maps based on the construction of certain positive non-Sum-of-Squares polynomials. We implement this algorithm in a numerically robust way and propose a working version on GitHub. We theoretically demonstrate that the maps produced by the algorithm are indecomposable, localized on the boundary of the positive cone and show that they are inequivalent with most other known PnCP maps. We numerically investigate their entanglement power, demonstrating notably that they are capable of detecting PPT entangled states that most criteria fail to detect. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.30426 [quant-ph] &nbsp; (or arXiv:2605.30426v1 [quant-ph] for this version) &nbsp; https://doi.org/10.48550/arXiv.2605.30426 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Mounir Rezig [view email] [v1] Thu, 28 May 2026 18:00:06 UTC (1,297 KB) Full-text links: Access Paper: View a PDF of the paper titled Detecting bipartite entanglement with PnCP maps and non-negative polynomials, by Ga\"el Mass\'e and 5 other authorsView PDFHTML (experimental)TeX Source view license Current browse context: quant-ph &lt;&nbsp;prev &nbsp; | &nbsp; next&nbsp;&gt; new | recent | 2026-05 References &amp; Citations INSPIRE HEP NASA ADSGoogle 

Detecting bipartite entanglement with PnCP maps and non-negative polynomials

detecting-bipartite-entanglement-pncp-maps-non-negative-polynomials

--> Quantum Physics arXiv:2605.30765 (quant-ph) [Submitted on 29 May 2026] Title:Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice Authors:Yaojian Chen, Chun-Yang Luan, Peilin Zheng, Xianghong Zeng, Jia-Yi Hou, Zhuo Fu, Yirong Jin, Fei Wang, Guangwen Yang, Dingshun Lv View a PDF of the paper titled Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice, by Yaojian Chen and 8 other authors View PDF HTML (experimental) Abstract:Quantum error correction (QEC) is transitioning from physical feasibility demonstrations to systems engineering challenges. Google has achieved below-threshold performance on distance-5/7 surface codes, while Riverlane and Rigetti have demonstrated hardware-integrated low-latency feedback loops. These milestones indicate that the core challenge of real-time decoding has shifted from algorithmic capability to system-level engineering. However, a substantial engineering gap remains between laboratory demonstrations and scalable fault-tolerant quantum computing (FTQC). This white paper addresses three questions: (1) Where are the real bottlenecks in real-time QEC: beyond average decoder speed, the constraints lie in QEC round time, tail latency, and end-to-end data path coordination; (2) How mature are mainstream decoder algorithms: we benchmark the major decoders for both surface codes and quantum low-density parity-check (qLDPC) codes, evaluating their real-time readiness; (3) What system stack do we propose: a six-layer reference architecture from syndrome acquisition to logical operations, with interface definitions and latency budget models. Our results quantify the gap between current decoder performance and real-time requirements, and identify the architectural choices needed to close it. Comments: Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2605.30765 [quant-ph] &nbsp; (or arXiv:2605.30765v1 [quant-ph] for this version) &nbsp; https://doi

Rigetti

Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice

real-time-quantum-error-correction-system-stack-architecture-algorithms

AdvertisementBanking &amp; financeBusinessHong Kong government’s venture fund eyes bigger bankroll after double-digit returnFinancial secretary says investment arm will also take lead on new offshore yuan-denominated venture capital fund3-MIN READ3-MIN ListenEnoch YiuPublished: 2:24pm, 1 Jun 2026Updated: 2:38pm, 1 Jun 2026The government’s investment arm achieved a double-digit internal rate of return last year, greater than many newly established venture capital funds, according to its CEO.“Many overseas funds have a J-curve performance, as they tend to suffer an initial loss before a gain,” said Clara Chan Ka-chai, CEO of Hong Kong Investment Corporation (HKIC). “But we have already bypassed the J-curve, as we have earned HK$2.3 billion [US$293 million] in 2024, while we have achieved a double-digit rate of return in 2025.”The strong performance, which will be detailed in HKIC’s annual report next month, came from many of its 200 investment projects achieving their growth targets, Chan said in a meeting of the Legislative Council’s Financial Affairs Panel on Monday.AdvertisementSeveral lawmakers during the session expressed support for Financial Secretary Paul Chan Mo-po’s plan, announced in his budget, to inject additional funding into HKIC, but also wanted more details.Chan, who attended the meeting on Monday, said the government would disclose the size of the injection later, but he added that it would be needed soon as HKIC had already invested almost the entire sum it had on hand.AdvertisementBacked by the government’s reserves, HKIC was established in 2022 to boost the city’s economy and innovation industry. As of March, it managed HK$62 billion (US$8 billion) in government funds.“The government reserves are now managed by the Hong Kong Monetary Authority, which has done a great job to achieve a very good return,” Chan said. “But the HKMA investment is mainly in finance vehicles, while the HKIC investment promotes innovation and technology development in the 

The Future of Quantum Computing

Dually tunable YBCO coplanar waveguide resonators based on helium-ion-generated Josephson inductances

Latest News

Detecting bipartite entanglement with PnCP maps and non-negative polynomials

Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice

Latest News

Dually tunable YBCO coplanar waveguide resonators based on helium-ion-generated Josephson inductances

Detecting bipartite entanglement with PnCP maps and non-negative polynomials

Real-Time Quantum Error Correction System Stack: Architecture, Algorithms, and Engineering Practice

Trending Stories

Get the Quantum News Newsletter

India National Quantum Mission