A selection of the most important recent news, articles, and papers about Quantum.
General News, Articles, and Analyses
1. Quantum compass could soon make GPS-Free navigation a reality – Electronic Products & TechnologyElectronic Products & Technology
https://www.ept.ca/2024/08/quantum-compass-could-soon-make-gps-free-navigation-a-reality/
(Thursday, August 22, 2024) “A milestone in quantum sensing is drawing closer, promising greater accuracy”
2. Quantum Network Runs 15 Days Interrupted Under New York Streets
Author: Berenice Baker
(Wednesday, August 28, 2024) “Quantum networking company Qunnect has made significant progress towards a quantum internet with a prototype quantum network under the streets of Brooklyn in New York City. Known as the GothamQ loop, the prototype network trial ran over a leased 34-kilometer-long fiber circuit for 15 continuous days.”
3. Quantum science and engineering expands across the nation with $39M from NSF | NSF – National Science Foundation
https://new.nsf.gov/news/quantum-science-engineering-expands-across-nation-39m-nsf
(Thursday, August 29, 2024) “The U.S. National Science Foundation is investing $39 million to help grow quantum research activities at more institutions across America through the NSF…”
Technical Papers, Articles, and Preprints
1. [2407.01182] A globally driven superconducting quantum computing architecture
https://arxiv.org/abs/2407.01182
Authors: Menta, Roberto; Cioni, Francesco; Aiudi, Riccardo; Polini, Marco; and Giovannetti, Vittorio
(Monday, July 01, 2024) “We propose a platform for implementing a universal, globally driven quantum computer based on a 2D ladder hosting three different species of superconducting qubits. In stark contrast with the existing literature, our scheme exploits the always-on longitudinal ZZ coupling. The latter, combined with specific driving frequencies, enables the reach of a blockade regime, which plays a pivotal role in the computing scheme.”
2. Quantum sensor detects magnetic and electric fields from a single atom – Physics World
https://physicsworld.com/a/quantum-sensor-detects-magnetic-and-electric-fields-from-a-single-atom/
Author: Isabelle Dumé
(Thursday, August 22, 2024) “New device is like an MRI machine for quantum materials, say physicists”
3. [2408.13687] Quantum error correction below the surface code threshold
https://arxiv.org/abs/2408.13687
Authors: Acharya, Rajeev; Aghababaie-Beni, Laleh; Aleiner, Igor; Andersen, Trond I.; Ansmann, Markus; Arute, Frank; Arya, Kunal; Asfaw, Abraham; Astrakhantsev, Nikita; Atalaya, Juan; Babbush, Ryan; Bacon, Dave; Ballard, Brian; Bardin, Joseph C.; Bausch, Johannes; Bengtsson, Andreas; Bilmes, Alexander; Blackwell, Sam; Boixo, Sergio; Bortoli, Gina; …; and Zobrist, Nicholas
(Saturday, August 24, 2024) “Quantum error correction provides a path to reach practical quantum computing by combining multiple physical qubits into a logical qubit, where the logical error rate is suppressed exponentially as more qubits are added. However, this exponential suppression only occurs if the physical error rate is below a critical threshold. In this work, we present two surface code memories operating below this threshold: a distance-7 code and a distance-5 code integrated with a real-time decoder. The logical error rate of our larger quantum memory is suppressed by a factor of Λ = 2.14 ± 0.02 when increasing the code distance by two, culminating in a 101-qubit distance-7 code with 0.143% ± 0.003% error per cycle of error correction. This logical memory is also beyond break-even, exceeding its best physical qubit’s lifetime by a factor of 2.4 ± 0.3. We maintain below-threshold performance when decoding in real time, achieving an average decoder latency of 63 μs at distance-5 up to a million cycles, with a cycle time of 1.1 μs. To probe the limits of our error-correction performance, we run repetition codes up to distance-29 and find that logical performance is limited by rare correlated error events occurring approximately once every hour, or 3 × 109 cycles. Our results present device performance that, if scaled, could realize the operational requirements of large scale fault-tolerant quantum algorithms.”
4. Open problem in quantum entanglement theory solved after nearly 25 years – Physics World
https://physicsworld.com/a/open-problem-in-quantum-entanglement-theory-solved-after-nearly-25-years/
Author: Daniele Iannotti
(Tuesday, September 03, 2024) “Non-existence of universal maximally entangled isospectral mixed states has implications for research on quantum technologies”