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• Single-Ion Error Correction Extends Qubit Lifetime 12.9-Fold

  A trapped-ion team reports autonomous quantum error correction that extended a logical qubit’s lifetime to 11.6 milliseconds under injected magnetic noise. The result exceeded the best physical-qubit lifetime without measurement or real-time feedback.

• Lai, Chen and Hung Verify Structured Hamiltonian Encodings at 256 Qubits

  A verifier certified 50 of 51 structured Hamiltonian block-encoding benchmarks within 30 minutes, including Ising and MaxCut instances with 256 system qubits. The paper also composes a verified block encoding and QSP wrapper into a circuit estimated at 1.52 million gates, with an error bound below 10⁻⁴ + (50/512) × 10⁻⁸.

• Jülich Team Shapes Transmon Pulses for 6.8-Nanosecond Gates

  Researchers at Forschungszentrum Jülich report single-qubit gates with 6.8-nanosecond pulses and fidelities above 99.98%. Their pulse-shaping method reduces leakage from unwanted transitions in a superconducting transmon.

• UTe₂ Measurements Establish a Tetracritical Point at 0.20 GPa

  Ultrasound measurements of uranium ditelluride reveal a previously missing superconducting phase boundary and establish a tetracritical point near 0.20 GPa. The results map where two superconducting order parameters coexist under pressure and magnetic field, without establishing whether the mixed state is topological.

• SkyWater Opens OnRamp for Quantum Startups Seeking Their First Wafers

  SkyWater announced OnRamp on October 27, offering selected early-stage quantum hardware teams no-cost engineering help to scope a foundry roadmap and paid access to early SP90 wafers. The program is aimed at photonics startups, university spinouts and grant-backed teams, with selection based on technical fit, readiness and available engineering capacity.

• Pitt Wins $4.385 Million for Quantum Cancer-Imaging Research

  The University of Pittsburgh and UPMC Hillman Cancer Center announced a two-year ARPA-H award to test whether entangled photons produced during radiation therapy can reveal tumor biology. ARPA-H lists the QTX project at up to $4.8 million, while UPMC reports an award of $4.385 million.

• IQM Entangles All 54 Qubits on Its Emerald Processor

  IQM says its cloud-accessible Emerald quantum computer prepared a Greenberger–Horne–Zeilinger state across all 54 qubits at once. The company reports a fidelity of 0.516 with readout error mitigation and says cloud customers can use the full-chip performance.

• Liu, Bai and Scarani Unify Quantum Smoothing Theories

  Mingxuan Liu, Ge Bai and Valerio Scarani present a framework that treats competing quantum state-smoothing approaches as different choices of prior correlations. Their paper, published in npj Quantum Information, uses extended Bayesian retrodiction to connect past and future measurement records.

• IBM Gate Patterns Bias Neighboring Qubits in New Tests

  A Scientific Reports study finds that two-qubit gate sequences on IBM quantum processors can bias measurements of nearby spectator qubits. The paper reports 40,000-experiment results for selected setups and a strong association between circuit configuration and measured outcomes.

• Alice & Bob Estimates 22,593 Cat Qubits for RSA-2048

  Alice & Bob researchers estimate that a fault-tolerant cat-qubit computer could factor RSA-2048 with 22,593 physical qubits in 3.14 days. The estimate depends on demanding error assumptions, including no bit-flips, and describes a machine that has not been built.

• UK Sets 15-Year Route to Put Quantum Systems in Space

  The UK’s Quantum Technology Roadmap for Space sets priorities for moving quantum timing, sensing and secure communications from prototypes towards space use by 2040. Published on 27 October, it lays out three development horizons and calls for flight demonstrations, stronger qualification capacity and supply-chain investment.

• South Korea Expands Quantum Testbeds Into Three Hubs

  South Korea launched a three-year plan to expand quantum communications testbeds into commercial, overseas and future-technology hubs. KT will lead domestic and future testing, while SK Broadband leads cross-border trials.

• NIH Opens Registration for $7.1 Million QuSAFE Challenge

  NIH opened registration on October 25 for QuSAFE, a $7.1 million competition to develop quantum-enabled sensing prototypes for preclinical safety testing. The challenge seeks measurements in human-cell laboratory models that could improve detection of biological signals relevant to drug toxicity and safety.

• Researchers Extend NV-Spin Memory to 565 Microseconds

  A team led by researchers at Ulm University reports extending coherence memory in an ensemble of diamond NV centers from 49 to 565 microseconds. Its pulse sequence also improves detection of weak alternating magnetic fields.

• Researchers Demonstrate a Single-Molecule Spin–Photon Interface

  Researchers report a carbene molecule that combines optical spin readout with millisecond-scale coherence at 4.5 K. The work demonstrates single-molecule addressability, while photon emission efficiency remains a limitation.

• RhymeQ Raises $2.2 Million to Bring Python Developers to Quantum

  RhymeQ has raised a $2.2 million pre-seed round and launched Rhyme, a Python-based tool for programming quantum computers. The company says its software compiles through NVIDIA CUDA-Q and is designed to work across multiple quantum processors.

• Paper Reports Sub-10⁻⁵ Bounds for Optical Bell Resources

  A paper proposes an optical quantum-computing architecture that separates verified Bell-resource preparation from online logical processing. In simulations, two level-2 conditions each have a one-sided 95% upper error bound below 10⁻⁵, with seven observed failures across two million accepted samples.

• Infleqtion Reports Tiqker Clock Ran More Than Two Weeks at Sea

  Infleqtion says its Tiqker optical atomic clock operated continuously aboard the U.S. Navy support vessel RV Merlin for more than two weeks during the Maritime Big Play Pacific exercise. The announcement describes testing in maritime conditions but gives no measured timing or navigation results.

• Chicago–IBM Team Maps Backaction with Three Measurements

  A University of Chicago and IBM team reports a protocol that learns how midcircuit measurements both record results and alter qubit states using strings of three repeated measurements. Tests on IBM processors found that the learned model predicted Pauli observables more accurately than a conventional confusion-matrix model.

• Researchers Pre-Train 64-Qubit Circuits with Pauli Propagation

  A team from RWTH Aachen University and DESY trained quantum circuits on classical computers before deploying them on IBM’s ibm_berlin processor. The paper tests the method on a two-dimensional Ising model and a generative model for handwritten digits.

• A Dissipative Controller Adds a Hidden Cost to Quantum Gates

  A theoretical study links noise from a dissipative classical controller to errors in quantum gates. Its models show a tradeoff between control error and entropy production, while leaving the cost in real hardware undetermined.

• Researchers Model Cavity-Loss Solver for MaxCut and MIS

  A paper proposes a cavity-based quantum solver that uses photon loss to help escape local minima in MaxCut and Maximum Independent Set. Numerical studies identify favorable parameter regions and estimate time complexities for the two problems.

• NIST Finalizes PQC Migration Guidance, Sets 2035 Cutoff

  NIST’s final IR 8547 sets a transition schedule for quantum-vulnerable public-key cryptography, while federal rules require prioritized systems to move sooner. The report recommends ML-KEM-768 for key establishment and describes how application guidance and hybrid methods fit into the transition.

• IBM and Rutgers Steer Quantum Chaos Across 100 Qubits

  IBM and Rutgers researchers used mid-circuit measurements and conditional resets to control quantum-chaotic dynamics on a processor with up to 100 qubits. Their Nature Physics paper reports a transition near a control probability of 0.5, while noting that noise obscures part of the quantum signal.

• Federal PQC Plan Deadline Passes, Compliance Still Unclear

  Federal agencies were due to submit post-quantum cryptography migration plans by October 22, but the deadline alone does not reveal whether they filed on time. An earlier requirement in the same memorandum tasked GSA with establishing an interagency working group, while a GAO report describes preparation gaps based on a review originating in September 2025.

• Fan and Pang Target Two Precision Limits in Quantum Thermometry

  Jingyi Fan and Shengshi Pang propose a theoretical protocol designed to attain both Heisenberg-limited precision and the Landau bound at low temperatures. Their approach uses linear couplings between central probes and a larger array, with the authors reporting that measurements on the central probes alone can achieve comparable precision.

• Mixed Initial States Trigger Sudden Entanglement Birth

  A study of qubit–environment interactions finds that mixed initial states can produce delayed entanglement, a behavior unavailable for pure initial qubit states in the same setting. Its numerical examples also show that commonly used entanglement witnesses can miss entanglement when their results are nonnegative.

• Roth Team Maps Arbitrary Atom Rearrangements onto Optical Lattices

  Alexander Roth and colleagues propose a coherent scheme for rearranging ultracold atoms in optical lattices using global tunneling pulses and local phase shifts. Their two-dimensional routing protocol scales in circuit depth as the square root of the number of lattice sites, but the work remains a theoretical proposal with demanding control requirements.

• Photonic Processor Classifies Quantum States by Stellar Rank

  A programmable photonic processor classified 180 single-mode quantum states as stellar rank zero or one using a quantum-kernel method. The experiment showed accurate classification despite imperfections, while the paper’s polynomial-resource guarantee depends on conditions that the experiment’s homodyne estimator does not satisfy.

• Adiabatic VQA Study Tests Entanglement Detection on Three Qubits

  A University of Granada-led study tests adiabatic-inspired training for variational quantum algorithms that classify entangled and separable three-qubit states. Its 25-qubit reference describes earlier methods, not a result demonstrated by the new work.

• MITRE and Oak Ridge Launch a Joint Computing Institute

  MITRE and Oak Ridge National Laboratory announced a joint institute for advanced computing, artificial intelligence and quantum research tied to U.S. national-security missions. The partners named three research areas but did not specify a budget, schedule or first projects.

• Gonçalves, Yang and Lin Find a Route to Chiral Pairing

  Miguel Gonçalves, Kun Yang and Shi-Zeng Lin propose a route to chiral superconductivity by hole-doping a Chern ferromagnet. Their calculations find a narrow, model-specific spin-orbit-coupling range in which skyrmion-like Cooper pairs could condense.

• Alice & Bob Team Maps a Dissipative Phase Diagram with 7x Fewer Solves

  A variational method cut the number of exact steady-state calculations needed to map a simulated dissipative phase diagram by a factor of seven. The paper also reports a further threefold reduction using a multipoint version and tests the methods on parameter fitting and a spin model.

• Quandela Names Quang Trung University for Vietnam’s First Quantum Computer

  Quandela and Vietnamese partner Quanova plan to deploy a MosaiQ photonic quantum computer at Quang Trung University, with support from Nam A Bank. The project also includes faculty training, dedicated courses and a residency program for students and researchers.

• Optical Experiment Recovers 10.3% of Lost State Purity

  A team used quantum state smoothing on an optical parametric oscillator to improve estimates of its hidden quantum state. The experiment reported 10.3% recovery of available state purity and 7.6% recovery of available squeezing.

• Qiskit 2.6 Brings Custom Compiler Passes to Its C API

  Qiskit 2.6 adds C API support for custom compiler passes, circuit serialization and user-defined quantum operations. The release also makes QPY v18 the default and advances IBM’s effort to reduce the SDK’s reliance on Python.

• UCLA Team Uses Arginine to Stabilize TaS₂’s Quantum Order at 330 K

  A UCLA-led study reports that arginine raises the temperature at which tantalum disulfide maintains a commensurate charge density wave to 330 kelvin. The researchers say the result suggests a molecular route to tuning quantum materials, but it does not demonstrate a working memory device.

• CoDecoder Cuts Quantum Decoding Time by Up to 124×

  Researchers report that CoDecoder, a neural front end for existing quantum error-correction decoders, reached a 124-fold speed-up in a benchmark on a bivariate-bicycle code. In registered tests, the hybrid approach also reduced decoding failures, but its results come from memory experiments and GPU-based timing rather than a live quantum processor.

• Hybrid Quantum Model Tracks Fermion Scattering Near Resonance

  A tensor-network study models fermion–antifermion collisions in a hybrid framework that encodes fermions in qubits and the scalar field in oscillator modes. Its simulations track a localized scalar excitation near resonance and find that a correlator-derived decay rate is close to the lattice prediction.

• One Transmon Connects Two Superconducting Waveguides

  Researchers at the Leibniz Institute of Photonic Technology demonstrated a superconducting transmon that mediates microwave-photon transfer between two separate waveguides. Tested at 10 millikelvin, the device operated with an input signal averaging about one photon near 6 gigahertz.