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• Intel Agrees to Acquire Classiq for Full-Stack Quantum Computing

  Intel announced a definitive agreement on October 26, 2026, to acquire quantum software company Classiq. The planned combination pairs Classiq’s quantum algorithm synthesis platform with Intel’s silicon spin-qubit work, with closing expected in the first half of 2027.

• Researchers Use Compression to Map Quantum Matter

  A team led by researchers at the University of California, San Diego, used lossless image compression to measure spatial complexity in quantum materials. The method detected peaks near integer and fractional quantum Hall transitions in graphene, but not the same signature in a control crossover.

• CV-DIPE Uses Homodyne Data to Compare Quantum States

  A paper describes a protocol for estimating the inner product of continuous-variable quantum states using local homodyne measurements at shared phase settings. Its sufficient bounds show improved accuracy scaling for Gaussian states, while simulations illustrate how estimation error varies with mode count and state family.

• SpinHex Projects 10,000 Logical Qubits on a 2.6 cm² Chip

  A SpinHex design study projects that a 2.6 cm² chip could host 10,000 logical spin qubits, assuming two-qubit gate errors of 0.01%. The proposed hexagonal architecture uses multielectron quantum dots as couplers, but its two-dimensional network has not yet been demonstrated.

• Researchers Demonstrate Optical Control of a ZnSe Donor Spin

  A team reports optical initialization, readout and coherent control of a single chlorine-donor electron spin in a ZnSe quantum well. The measurements include Rabi oscillations, Ramsey interference and a charge-limited relaxation time of 18.5 microseconds.

• Neural Wavefunctions Map Quantum Hall Phases—and Their Fragility

  A new neural-network study compares fractional quantum Hall states across filling factors while including Landau-level mixing. Its highest reported overlaps belong to specific small-system comparisons; the candidate-state overlaps fall as mixing increases.

• Yang's Counterexample Defeats a Quantum-Channel Optimality Conjecture

  Jianting Yang’s paper, published in Quantum on October 28, 2026, gives a two-dimensional counterexample to an optimality test proposed by Bryan Coutts, Mark Girard and John Watrous. The example shows that a spectral-sign calculation can fail to certify an optimal quantum channel when the error matrix is rank-deficient.

• Wolfspeed Offers Transparent SiC for Quantum-Computing Applications

  Wolfspeed says its optical-grade transparent silicon carbide substrates are commercially available for optical applications, with quantum computing among the areas being explored. Its announcement describes a material platform, not demonstrated quantum-device performance.

• Three Researchers Derive a Unique Quantum Bayes Rule

  A paper posted to arXiv on October 29 proves that four consistency requirements uniquely select the Petz transpose map for quantum retrodiction. The result applies to finite-dimensional channels and leaves a family of rotated maps when one requirement is dropped.

• Shao and Motter Rework Entanglement Percolation

  Yanxuan Shao and Adilson E. Motter propose a power-of-choice protocol for entanglement percolation in quantum communication networks. Their paper says reversing a selection rule can bring the percolation transition earlier, reduce the entanglement resources required and allow implementation using local information without appreciable loss of performance.

• New York Study Puts State Second in Three Quantum Measures

  A New York State study ranks the state second among nine benchmarks in operating quantum entities, research groups and patent families, while placing it third in state commitments. It identifies statewide coordination, facility access, technician training and capital as gaps, and recommends appointing an owner for the state’s quantum agenda.

• OQTOPUS Adds Buffer-Qubit Reservations Against Crosstalk

  A paper describes adding buffer-qubit reservations to OQTOPUS, a software stack for running quantum circuits from multiple users on one chip. In a test on one superconducting quantum computer, observable dephasing changes appeared only at qubits adjacent to the attacker circuit; the authors also tested the allocator’s buffer reservations.

• Sloan and Sipe Model Cleaner Squeezed Light With Coupled Rings

  M. Sloan and J. E. Sipe model how a second microring resonator could suppress noise in squeezed light or improve the alignment of the process that generates it. Their analysis uses a five-resonance approximation and describes a theoretical model, not an experimental device demonstration.

• Sound Emission Can Increase Kelvin Waves on a Superfluid Vortex

  A Gross–Pitaevskii simulation finds that sound can leave a superfluid vortex with more Kelvin waves even as those waves lose energy. In a reflecting cavity, shifting the initial sound phase reverses the transfer, while the paper’s example rate for spontaneous splitting is extremely small.

• Yi and Zhou Use Parity to Simplify Green’s-Function Measurements

  Changhao Yi and Cunlu Zhou describe a parity-based protocol for estimating many-body Green’s functions without ancilla qubits or controlled time evolution in the measurement circuit. Numerical simulations test the method on Fermi–Hubbard and XXZ models, while the paper identifies hardware demonstrations and improved noise guarantees as next steps.

• Photon Pairs Improve Loss Estimates in Whispering-Gallery Resonators

  A theoretical study finds that indistinguishable photon pairs can improve estimates of optical loss in a whispering-gallery-mode resonator under particular coupling conditions. The modeled advantage depends on retaining information from photon-loss outcomes and does not extend to every operating regime.

• Tanay Roy’s Protocol Lets a Quantum Gate Wait for Its Recipient

  Tanay Roy describes a protocol that distributes encoded shares before a recipient is chosen, then lets one selected node use a quantum gate after receiving a key register. The paper’s two-candidate threshold scheme depends on qudit dimension and, at the smallest flat phase angle, holds automatically for even dimensions but has a condition for odd ones.

• Kun Wang Sets Out Three Protocols to Compare Remote Bosonic States

  Kun Wang compares three local-measurement protocols for estimating the inner product of separated continuous-variable quantum states. Their theoretical sample bounds favor coordinated Haar measurements, while homodyne measurements use more accessible optical components.

• NowSecure Finds 97% of 136,711 Mobile Apps Lack Detectable PQC

  NowSecure’s analysis of 136,711 iOS and Android apps found that 96.9% had no detectable post-quantum cryptography code or libraries. The company also flagged more than 3,100 apps using weak encryption, while cautioning that its binary scan cannot establish whether detected code runs.

• Researchers Extend Bell Tests to Certify Majorana Operators

  Patryk Michalski and co-authors propose Bell inequalities that can device-independently certify Majorana operators under specified mathematical conditions. The theoretical method also identifies a partial-transposition ambiguity that standard self-testing definitions do not capture.

• Quantum X Labs Starts QEC Experiments on Arbel Processor

  Quantum X Labs has begun quantum error-correction experiments on the Arbel superconducting processor at Israel’s Quantum Computing Center. The company says the work is an early hardware test, not a demonstration of real-time error correction or fault-tolerant computing.

• NV Centers Map Stress Around One Diamond Dislocation

  Researchers used nitrogen-vacancy centers to map four stress quantities around a single dislocation in diamond. Their measurements agree with elasticity theory and resolve stress variations near 10 megapascals.

• Harvard Physicists Set Out Exponential Speedups for Signal Sensing

  A quantum sensing protocol described in Physical Review X can estimate multiple properties of a classical signal from one dataset, with below-vacuum-level noise. For specially structured waveform priors, the authors prove an exponential reduction in measurement requirements compared with strategies without entanglement.

• PASQAL’s Rydberg Array Maps Ising Meson Spectra

  A team affiliated with PASQAL used a programmable array of Rydberg atoms to study excitation spectra in an Ising chain and a two-chain ladder. The measured signatures are consistent with E8 mass ratios in the chain and a D8(1) bound-state spectrum in the ladder.

• He, Wang, Song and Gu Set a CSS-Code Decoupling Criterion

  A new paper identifies inter-layer gluing as an obstacle to separating higher-dimensional, translation-invariant topological CSS codes into toric-code stacks. Its authors give a criterion for decoupling and an algorithm to construct the circuit.

• Arclight Authors Compile Imaginary-Time Filters for Reuse

  A paper by Hengyue Li and colleagues describes a compiled approach to probabilistic imaginary-time evolution whose circuit size per attempt stays fixed as evolution time changes. Benchmarks show that its cost per accepted output depends on postselection and the comparison method, with grouped filtering outperforming it on the reported XYZ example.

• Innsbruck Team Reports Trapped-Ion Gate Errors Below 0.5%

  Researchers report two-qubit trapped-ion gates with error rates below 0.5% in crystals containing up to 12 ions. Their structured-light method is designed to reduce unwanted coupling to nearby collective motion modes while preserving the ability to address individual ions.

• Oxford Stores Remote Ion Entanglement in Calcium for 10 Seconds

  An Oxford quantum-network experiment transferred entanglement between remote strontium ions to calcium memory qubits and stored it for about 10 seconds. The study also created mixed-species entangled states involving as many as four matter qubits.

• Three Users Share a QKD Network Through a Passive Circulator Hub

  Researchers demonstrated pairwise quantum key distribution among three users through a passive optical circulator hub. The fiber links spanned 20 to 25 kilometers, and all three pairs produced positive secret-key lengths using BB84.

• Researchers Demonstrate Transmitter-Independent QKD Over 27 km

  A proof-of-principle experiment tested a transmitter-device-independent quantum key distribution protocol over 27 kilometers of spool fiber. The paper reports an asymptotic key rate of 410 bits per second.

• Alice & Bob Tests Three Cat-Qubit Demonstrators for PROQCIMA

  Alice & Bob reports operating three cat-qubit demonstrators for Phase 1 of France’s PROQCIMA programme. The tests covered error-correction operations, but the measured logical error rate has not yet fallen below threshold.

• Scottish Widows Fund Expected to Include Two UK Quantum Companies

  The CG Scottish Widows Growth LTAF has announced its first investments in UK science and technology, with Oxford Quantum Circuits and Quantum Motion among four companies expected to be included. Aberdeen Investments has appointed IP Group to manage a UK venture-growth portfolio within the fund.

• Terahertz Light Separates Electron and Hole States in Vortex Cores

  A Rutgers and Estonian team used terahertz Faraday spectroscopy to distinguish electron-like and hole-like quantum states in iron telluride–selenide superconductors. The measurements reveal how those vortex-core states change with selenium content, even when the films have nearly identical superconducting temperatures.

• UbiQD Wins $200,000 Grant for a Single-Photon Source

  UbiQD has received a $200,000 New Mexico award to develop a quantum-dot light source that sends single photons directly into optical fiber. The Los Alamos company plans to use the grant for optical equipment, device prototyping and performance measurements.

• Qblox Reports Sub-4-Microsecond GPU–Quantum-Control Latency

  Qblox says its Cluster control system reached round-trip latency below 4.0 microseconds with an NVIDIA RTX PRO 6000 Blackwell GPU and below 7.2 microseconds with DGX Spark. The October 22, 2026 announcement describes a GPU-linked control setup for calibration and quantum-error-correction workloads, but does not detail a test on a running quantum processor.

• UCF Wins $400,000 DOE Grant for Partially Fault-Tolerant Tools

  UCF assistant professor Siyuan Niu’s team received a $400,000 Department of Energy grant to develop software for partially fault-tolerant quantum computers. The planned open-source framework will compile electron simulations, decode errors using GPUs and estimate the quantum and classical resources required.