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August 5, 2026.

60 quantum research items collected on 2026-08-05; hardware, control, and industry signals routed.

102 items · Quantum, Chips, Power · All briefs

Quantum

60 quantum research items collected on 2026-08-05; hardware, control, and industry signals routed.

Hardware and Error Correction

  • Separating quantum circuits from classical LLMs

    Modern large language models - transformers and diffusion language models - are built around two canonical algorithmic tasks: prediction and generation. We prove unconditional separations between low-depth quantum computation and the corresponding bounded-resource classical language-model architectures in both regimes. Concretely, we exhibit the following: 1. Distributional...

  • Joint spectral characterization of SPDC photon pairs near 2 $μ$m in (Al)GaAs-on-insulator waveguides

    Integrated photon-pair sources are a core component of chip-based quantum computing, communication, and metrology. Although such sources have been demonstrated at conventional telecom wavelengths, the 2 $μ$m band remains comparatively less explored, despite offering advantages for free-space quantum communication, low-loss transmission in emerging fiber networks, and integra...

  • Real-time decoding of quantum error correction codes using high-performance computing

    Quantum error correction (QEC) is indispensable for building scalable fault-tolerant quantum computers. Effective QEC demands stringent real-time decoding: the decoder must process syndrome measurements and determine corrections within a time scale--typically on the order of microseconds, to avoid data backlog. Scaling to large number of logical qubits further necessitates s...

  • Exact Tradeoff Between Quantum Error Correction and Quantum Darwinism: An Information-Theoretic No-Go Theorem

    Quantum error correction (QEC) and Quantum Darwinism describe opposing consequences of system-environment interactions: QEC seeks to preserve logical quantum information, whereas Quantum Darwinism explains the emergence of objective classical information through its proliferation into the environment. Despite their common physical origin, no direct quantitative connection be...

  • CNOT-Distance is NP-complete under all-to-all connectivity

    Given $A\in\operatorname{GL}(N,2)$ and an integer $K$, we ask whether $A$ can be implemented by at most $K$ CNOT gates on fixed labelled wires with all-to-all connectivity. We prove that this problem is NP-complete. From a finite simple graph $G=(V,E)$, we construct an upper-unitriangular matrix $A_G\in\operatorname{GL}(2|V|+|E|+1,2)$ satisfying $\ell_{\mathrm{CNOT}}(A_G)=2|...

  • Controllable interaction between photons and distant spins via vacuum Rabi oscillations

    Vacuum Rabi oscillations between a single photon and a single spin demonstrate the capability of harnessing light-matter interaction at the level of a single quantum of energy. Since the observation of strong spin-photon coupling in gate-defined quantum dots, probing this interaction in the time-domain has been a major objective. Here, we carefully engineer a device composed...

  • Uncovering Non-Gaussianity through Multi-Copy Symmetries

    Gaussian states are fundamental in continuous-variable quantum information, yet characterizing non-Gaussianity remains challenging due to the non-convexity of the Gaussian set. Existing witnesses typically rely on Wigner negativity or other information-theoretic quantities. In this work, we develop a group-theoretic, multi-copy approach to detect non-Gaussianity in bosonic s...

  • Bimodal non-Gaussian photonic states from a single quantum emitter in a waveguide

    We investigate the generation of deterministic and heralded non-Gaussian states of light, using a single two-level system coupled to a chiral waveguide. We study the case of a single two level system driven by pulsed coherent and squeezed drive in a chiral waveguide. For coherent input pulses, we show that the emitter can deterministically generate Wigner-negative states, al...

Control and Quantum-AI Integration

Commercial and Industry Context

  • Non-Relativistic Quantum Electrodynamics of Atoms in a Rotating Ring Cavity

    In this paper, we derive a quantum optics model in a non-inertial rotating ring cavity from first principles. We begin with the Dirac equation in curved spacetime, add minimal coupling to the electromagnetic field, and then find the Dirac Hamiltonian for the generalized Born metric. We then formally take the non-relativistic limit by way of Foldy-Wouthuysen transformations a...

  • TNASS: Tensor Network Active Space Selection with the Entanglement Feature

    The quality of multi-scale modelling techniques in molecular electronic structure calculations, such as embedding and subspace methods, relies upon the chosen active space. The automation of active space selection is vital for ensuring the accuracy, reproducibility, and scalability in such calculations. In this work, we introduce Tensor Network Active Space Selection using t...

  • Israel Launches National Quantum Computer Tender as Part of Broader AI Sovereignty Strategy

    <a href="https://thequantuminsider.com/2026/08/05/israel-launches-national-quantum-computer-tender-as-part-of-broader-ai-sovereignty-strategy/" rel="nofollow" title="Israel Launches National Quantum Computer Tender as Part of Broader AI Sovereignty Strategy"><img alt="A close-up of the Israeli flag waving on a flagpole against a clear blue sky." class="webfeedsFeaturedVisual...

  • IonQ and Sandia National Laboratories Partner on Quantum Technology Research

    <a href="https://thequantuminsider.com/2026/08/05/ionq-sandia-quantum-technology-research-partnership/" rel="nofollow" title="IonQ and Sandia National Laboratories Partner on Quantum Technology Research"><img alt="IonQ logo" class="webfeedsFeaturedVisual wp-post-image" height="709" src="https://thequantuminsider.com/wp-content/uploads/2026/08/2026-08-05_12-42.png" style="dis...

  • enQase and Light Rider Collaborate on Quantum-Safe Communication Infrastructure

    <a href="https://thequantuminsider.com/2026/08/04/enqase-light-rider-quantum-safe-communication-infrastructure/" rel="nofollow" title="enQase and Light Rider Collaborate on Quantum-Safe Communication Infrastructure"><img alt="enQase logo" class="webfeedsFeaturedVisual wp-post-image" height="734" src="https://thequantuminsider.com/wp-content/uploads/2026/08/2026-08-03_14-06.p...

  • Quantum Corridor, Ciena and Toshiba Test 1.6 Tb/s Quantum-Safe Network Encryption

    <a href="https://thequantuminsider.com/2026/08/04/quantum-corridor-ciena-toshiba-1-6-tbps-quantum-safe-optical-encryption-live-network/" rel="nofollow" title="Quantum Corridor, Ciena and Toshiba Test 1.6 Tb/s Quantum-Safe Network Encryption"><img alt="Quantum Corridor, Ciena, and Toshiba logo" class="webfeedsFeaturedVisual wp-post-image" height="708" src="https://thequantumi...

  • IQM Confirms 2026 Outlook After Public Listing, Citing More Than €102 Million in Orders

    <a href="https://thequantuminsider.com/2026/08/04/iqm-confirms-2026-outlook-after-public-listing-citing-more-than-e102-million-in-orders/" rel="nofollow" title="IQM Confirms 2026 Outlook After Public Listing, Citing More Than €102 Million in Orders"><img alt="IQM" class="webfeedsFeaturedVisual wp-post-image" height="700" src="https://thequantuminsider.com/wp-content/uploads/...

  • Did IBM CEO’s Quantum Timeline Prompt Jim Cramer to Exit Bitcoin?

    <a href="https://thequantuminsider.com/2026/08/04/did-ibm-ceos-quantum-timeline-prompt-jim-cramer-to-exit-bitcoin/" rel="nofollow" title="Did IBM CEO&#8217;s Quantum Timeline Prompt Jim Cramer to Exit Bitcoin?"><img alt="Cramer" class="webfeedsFeaturedVisual wp-post-image" height="941" src="https://thequantuminsider.com/wp-content/uploads/2026/08/Cramer-1.png" style="display...

Unrouted Items

  • Realified tensor networks: quantum circuit simulation on real-valued matrix accelerators

    Tensor-network contraction simulates quantum circuits, but modern matrix accelerators (NPUs, TPUs) expose only real GEMM pipelines, so the complex networks of quantum simulation must be reconstructed in software. We resolve the mismatch by a realification rewrite that maps any complex tensor network to a real one. At each merge of two complex tensors, a rank-3 structure tens...

  • A lower bound on the classical simulation cost of star-network correlations

    It is well established that quantum strategies outperform classical ones in several communication tasks. We study the quantum communication complexity of correlations arising from joint measurements on quantum systems distributed across a star network, where several parties each send a quantum system to a central node. We introduce an exclusion task that can be solved perfec...

  • A quantum game of telephone

    Characterizing multinode quantum networks without ubiquitous local entanglement sources presents significant experimental challenges. We introduce ``quantum telephone,'' an iterative ancilla-assisted process tomography protocol that leverages intermediate detection events, effectively treating previously probed links as ancillae for subsequent links. Implemented on a deploye...

  • High-level quantum structured programs as quantum registers compositions

    Current quantum programs are mainly designed at the level of quantum gates acting on individual qubits; on a large scale and for complex problems this may involve a high cognitive load on the programmer, making the program specification nontrivial and error-prone. In this context, providing quantum programming with higher abstraction mechanisms will assist in making this tas...

  • Few-photon degenerate parametric resonance in a two-tone driven microwave resonator

    Multi-tone external driving offers a route to parametric physics without directly modulating the device. However, the validity of the parametric response in the few-photon regime remains underexplored. Here, we apply two coherent microwave tones to a Josephson-junction Kerr oscillator and stimulate degenerate parametric downconversion via four-wave mixing. Using transmission...

  • Interplay between teleportation fidelity and basis-independent coherence in maximally sliced states under decoherence

    The influence of environmental decoherence on quantum teleportation is investigated by considering the three-qubit Maximally Sliced (MS) state as the shared entangled resource. Using the Kraus operator formalism, analytical expressions are derived for the teleportation fidelity under amplitude damping and phase damping channels. The corresponding basis-independent coherence...

  • Geometric-Symmetry Logical Gate and Local-Probe Selectivity in the Three-Leg AKLT Ladder

    Symmetry-protected topological (SPT) phases provide a platform for encoding quantum information in protected boundary degrees of freedom. Here we study the three-leg Affleck-Kennedy-Lieb-Tasaki (AKLT) ladder as an exactly solvable SPT system with on-site symmetry $SO(3)\times \mathbb{Z}_2$. Using an exact matrix product state construction, we characterize the symmetry action...

  • Separable States Violate the Complementary-Quantum Correlation Conjecture

    Correlations measured in complementary local bases provide an experimentally accessible probe of the total correlations in a bipartite quantum state. The complementary-quantum correlation conjecture asserts that the sum of two such classical mutual informations never exceeds the premeasurement quantum mutual information. We disprove this conjecture in every local dimension $...

  • Impossibility of Perfectly Complete Many-Round Key Agreement in the QROM

    This paper proves that it is impossible to construct perfectly complete quantum key agreement protocols (QKA) from quantumly secure one-way functions (OWFs) in a black-box manner. Specifically, consider any protocol in which Alice and Bob exchange only classical messages, make at most $q_{\mathsf{A}}$ and $q_{\mathsf{B}}$ quantum queries, respectively, to a Boolean-valued ra...

  • Optimal and Deterministic Quantum Search on the Simplex of Complete Graphs

    The simplex of complete graphs, also known as the first-order truncated simplex lattice, is a network of $M+1$ identical complete graphs, each with $M$ vertices, such that each clique contains an edge or bridge to every other clique. It contains $N = M(M+1)$ vertices, and previous asymptotic results using a continuous-time quantum walk to search this graph for a single marke...

  • Preserving Symmetry: Spontaneous Symmetry Breaking through Decoherence

    Solids appear to have localised centres of mass, yet many-body quantum theory describes them using translationally symmetric models that preclude localisation. Conventionally, this is resolved through spontaneous symmetry breaking by introducing an interaction with a semiclassical environment that breaks the symmetry. In the thermodynamic limit, the interaction can be remove...

  • Cavity control of quantum phase transitions in a two-dimensional kondo lattice

    Cavity quantum electrodynamics offers a route to control quantum phases by using vacuum fluctuations of confined electromagnetic fields. In particular, planar cavities based on polar van der Waals materials can generate strongly confined modes and are promising for controlling two-dimensional correlated materials. Recently, moiré materials have become central platforms for s...

  • Entanglement Distillation of some Rank-Five Symmetric NPT States in Two-Qutrit Systems

    Entanglement distillation is a fundamental task in quantum information processing. In this work, we investigate the distillability properties of a class of two-qutrit symmetric NPT states of rank five. We resolve the 1-distillability problem for this class by proving that the previously open interval of the eigenvalue parameter is 1-undistillable. For the 2-distillability, w...

  • Fidelity-Based Robustness Margins for Finite-Time Quantum Control

    We develop a structure-specific fidelity-threshold robustness margin for finite-dimensional closed quantum systems under piecewise-constant coherent control. A scalar physical parameter may perturb the drift, a control Hamiltonian, or another declared Hamiltonian component across the control horizon. A differential sensitivity bound for trace-amplitude gate fidelity yields a...

  • DAMPyF: a Python implementation of the DAMPF method for the simulation of open-system dynamics

    DAMPyF is an open-source Python implementation of the dissipation-assisted matrix product factorization (DAMPF) method, a tensor-network-based approach for the numerically exact simulation of finite-dimensional quantum systems coupled to bosonic environments. The method relies on a pseudomode representation of structured reservoirs and a matrix-product-state representation o...

  • Quantum Impurities as Probes of Finite-Temperature Fluctuations in Two-Dimensional Bose Gases

    Two-dimensional quantum gases provide a distinctive setting in which enhanced thermal fluctuations, finite-size effects, and two-body bound-state formation are intrinsically intertwined. In this work, we study a single attractive impurity immersed in a finite, weakly interacting two-dimensional Bose gas, where finite size stabilizes a nonzero condensate fraction by introduci...

  • Iterative linear quadratic regulator on SU(N) for multi-qubit gate synthesis

    In quantum optimal control theory, gradient-based trajectory optimization techniques have proven versatile in designing multi-qubit quantum gates. Furthermore, incorporating the underlying Lie-group structure can accelerate the optimization process. In this work, we adapt the Lie-group formulation of the iterative linear quadratic regulator (iLQR) to the special unitary grou...

  • Entangling Topological Invariants

    An isolated occupied multiplet may admit local tensor-product descriptions without a globally consistent subsystem structure. We characterize the obstruction by comparing the transition functions of the occupied multiplet with those generated by independent basis changes in the two candidate subsystems. When a decomposition into rank-one sectors over a closed surface is spec...

  • Sample-half-inserted quantum interferometer

    Quantum technologies have been widely recognized as unprecedented opportunities for ultra-high precision metrology. As a celebrated example in modern quantum optics, the Hong-Ou-Mandel (HOM) interferometer is well-known for enabling temporal resolutions on the attosecond scale. However, the relatively low Fisher information per trial in ordinary HOM measurements typically ne...

  • Generation and Enhancement of Bipartite and Tripartite Entanglement in an Electro-Optomechanical Ring Cavity

    This study investigates the generation and enhancement of quantum entanglement in an electro-optomechanical ring cavity system. The setup integrates two Coulomb-coupled mechanical resonators, which serve as the fundamental mechanism for the generation of bipartite and tripartite entanglement via charge mediated coupling. We then demonstrate the significant enhancement of thi...

  • Gravitational redshift as a quantum channel: modeling the effects of gravitational redshift in quantum optics

    The gravitational frequency shift of light is well understood in the theory of classical electromagnetism. Nevertheless, its description in quantum theory is not yet fully developed. Recent work pointed out inconsistencies in previously developed models aimed at describing gravitational redshift as an effective multi-mode mixer (MMM) acting on modes of light, however, a comp...

  • Matrix Product Evolution: A Method for Simulating Quantum Circuits Using Tensor Networks

    Classical simulation of quantum circuits is an essential tool in quantum information science, but its applicability is constrained by the exponential growth of the Hilbert space and the entanglement structure of quantum states. In this work, we introduce Matrix Product Evolution (MPE), a tensor-train representation of quantum circuits constructed along the circuit depth rath...

  • Mesoscopic Quantum Communication via Photon-Number Moments

    Mesoscopic optical states are a promising resource for quantum communication, combining robustness against losses with the preservation of genuine quantum features. Here, we propose a quantum communication protocol in which information is encoded in the first and second moments of the photon-number distributions of classical optical states, and then decoded by photon-number-...

  • The geometry of absolute separability and other convex matrix properties from spectrum

    We investigate the geometric structure of the set of spectra of bipartite absolute separable states ($\mathrm{ASEP}_{m,n}$) and absolute positive partial transpose states ($\mathrm{APPT}_{m,n}$), i.e., bipartite quantum states that remain separable or PPT respectively, under all global unitary transformations. First, we establish general geometric properties of absolute conv...

  • Single-molecule strong optomechanical regimes in SERS via hybrid plasmonic cavities

    We identify enhanced strong coherent Surface-Enhanced Raman Scattering (SERS) interactions facilitated by hybridized metallo-dielectric cavities with a resonant fluorescent molecule. By illuminating a detuned electronic transition near saturation via a narrowband hybrid plasmonic mode, we observe enhanced splittings in the Stokes and anti-Stokes spectra, revealing strong opt...

  • Analysis of Superradiance-Based Quantum Metrology under Independent Markovian Pure Dephasing

    Recently, a DC magnetometry protocol utilizing $N$-spin-ensemble superradiance was proposed. This method physically amplifies the acquired signal, suppressing estimation errors from measurement noise and achieving $\mathcal{O}(1/N)$ precision scaling when measurement noise dominates quantum fluctuations. However, quantum metrology is generally vulnerable to independent Marko...

  • Factorization of Exclusive-Sum-Of-Products Expressions with Rectangle Covering to Reduce Quantum Circuit Cost

    The implementation of quantum circuits is currently very expensive, especially due to the usage of large Toffoli gates. Therefore, it is critical to optimize circuit costs by factoring expressions as they become more complex. In the proposed algorithms to factor ESOP expressions, each product term is converted into a cell in a 2D matrix, and optimal factored AND/EXOR solutio...

  • Characterizing pairwise swapping capabilities of dense coding channels

    We introduce a novel multipartite entanglement-assisted classical communication task, referred to as dense coding swapping, in which legitimate parties collaboratively swap the dense codeability from one communication channel to another through suitable joint unitary operations. Due to the dense coding (DC) exclusion principle, the scheme enhances the dense codeability of a...

  • Correlating spin and optical properties of quantum emitters in hBN

    Optically addressable spin defects in hexagonal boron nitride (hBN) are well suited for near-surface quantum sensing. They offer bright, wavelength-tunable single-photon emission with high optically detected magnetic resonance (ODMR) contrast at room temperature. Here we controllably synthesise a high density of spin-complex defects in carbon-doped hBN flakes. We find that t...

  • Heralded Free-Electron Writing of the Most Subradiant State in an Atomic Array

    The most subradiant eigenstate of a finite subwavelength atomic chain in free space, protected by strongly suppressed radiative decay, offers a powerful resource for photon storage, quantum sensing, and many-body quantum optics. Yet its optical preparation is hindered by the simultaneous need to match a wave vector outside the light cone and a nonuniform envelope. Here, we s...

  • Texas Quantum Summit to Bring Industry, Government and Academic Leaders Together at UT Dallas

    <a href="https://thequantuminsider.com/2026/08/05/texas-quantum-summit-to-bring-industry-government-and-academic-leaders-together-at-ut-dallas/" rel="nofollow" title="Texas Quantum Summit to Bring Industry, Government and Academic Leaders Together at UT Dallas"><img alt="" class="webfeedsFeaturedVisual wp-post-image" height="1599" src="https://thequantuminsider.com/wp-conten...

  • Horizon Quantum Reports Second Quarter 2026 Financial Results

    <a href="https://thequantuminsider.com/2026/08/04/horizon-quantum-reports-q2-2026-financial-results/" rel="nofollow" title="Horizon Quantum Reports Second Quarter 2026 Financial Results"><img alt="Horizon Quantum" class="webfeedsFeaturedVisual wp-post-image" height="703" src="https://thequantuminsider.com/wp-content/uploads/2026/08/2026-08-04_19-01.png" style="display: block...

Chips

45 chip stack items collected on 2026-08-05; memory, packaging, compute, and foundry signals routed.

Compute Accelerators

Memory and Advanced Packaging

Foundry, Tools, and Capex

Unrouted Items

Power

17 power layer items collected on 2026-08-05; data center load, grid, generation, and cooling signals routed.

Data Center Power Demand

  • New York imports more electricity from Canada after high-voltage transmission line opens

    On July 3, 2026, the New York Independent System Operator (NYISO) imported 52 gigawatthours (GWh) of electricity from Canada, the most traded between the two areas since January 2025. Some of the imported electricity flowed along the new Champlain Hudson Power Express (CHPE) transmission line between Quebec, Canada, and New York City, which officially reached commercial oper...

Grid and Generation

Unrouted Items

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