July 7, 2026

Logical Spectroscopy: Lifted-Product Codes with Addressable Bases

Quantum LDPC memories can encode many logical qubits, but dimension alone does not make them usable: applications need explicit conjugate logical operators with structured labels and physical representatives. For hypergraph-product (HGP) codes this structure is transparent, since the input matrices are binary and can be row-reduced over F_2. Abelian lifted-product...

Quantum Computational Resources and Conformal Field Theory: Unifying Spins, Bosons, and Fermions

Characterizing a quantum state through the lens of quantum resources provides an information-theoretic perspective on many-body systems. While quantum entanglement serves as the paradigmatic example of a quantum resource, recent studies have shown that quantum magic, a resource for universal quantum computation, can capture aspects of many-body states complementary to those...

Routing Anonymity and Identifiability of Noisy Quantum Hardware

Present-day quantum computing is cloud-based, where a user submits a circuit to a service provider's proprietary backend hardware. While providers may wish to hide implementation details, scheduling choices, or even which physical device was used, noisy finite-shot outputs can carry backend-specific fingerprints: information imprinted in the classical output distribution tha...

Spectral-topology-induced criticality in non-Hermitian fermionic metals

Quantum matter emerges from the interplay of fluctuations, topology, and entanglement, which - in equilibrium - governs quantized transport, universal criticality, and topological classification. Non-Hermitian systems, widely explored in platforms ranging from electric circuits to photonics, are intrinsically out-of-equilibrium, and display fundamentally new phenomena, inclu...

Complementary 3D color codes for transversal quantum logic

Transversal logical gates provide a direct route to fault-tolerant quantum computation, but the Eastin-Knill theorem forbids a universal transversal gate set within a single quantum error-correcting code. We propose a hybrid architecture based on the tetrahedral three-dimensional color code and its Hadamard-transformed counterpart, which we call the H-tetrahedral code. The t...

Transmon Phase Gates Controlled by Superconducting Soliton DAC

We introduce a superconducting digital-to-analog converter (DAC) that filters control noise, provides native multiplexing, performs quantum gates in nanoseconds, and can be controlled by CMOS. This is achieved by transducing a trapezoidal drive pulse into a superconducting soliton, which is then held in the DAC load loop, applying flux to a mutually-coupled superconducting q...

Super-molasses returns: All optical near-resonance laser cooling and trapping of neutral atoms from background vapor

Laser cooled and trapped atoms have been the workhorse of atomic physics for the past four decades. The predominant method has been the highly versatile Magneto-Optical Trap. We describe an alternative laser trap involving a simple geometry of collimated laser beams that provides both a velocity and position dependent restoring force such that a dense cloud of cold atoms is...

Photonic Cluster State Generation from a Quantum Dot Emitting in the Telecom C-band

Photonic cluster states are a key resource for photonic quantum information processing. So far, deterministic generation of these states has been limited to the near-infrared wavelength range. To achieve quantum advantage in communication while maintaining compatibility with silicon photonics, operation in the telecom wavelength range is required. In this work, we demonstrat...

Efficient classical simulation of two-dimensional long-range systems: Rydberg arrays and beyond

In variational Monte Carlo (VMC) calculations of N-site quantum systems with arbitrary all-to-all two-body interactions, evaluating the local energy generally costs O(N^3). We introduce a new framework that reduces this cost to O(N) for tensor network states, capable of scalable and accurate computation of real-time dynamics and ground states. As a result, we obtain ac...

Canonical quantization of neurons

Canonical quantization provides a systematic procedure for constructing quantum models from classical Hamiltonians. Here, we apply this principle to a fundamental computational primitive of machine learning: the neuron. Specifically, by viewing a neuron as a composition of an energy function and an activation function, we quantize this model by replacing the energy function...

Contraction and Expansion Values of Quantum Channels

The contraction coefficient of the trace distance is a central tool in quantum information, quantifying how strongly a quantum channel degrades the distinguishability of states. However, being an extremal ratio, it captures only the most optimistic behaviour of the channel and is often trivial, even for very noisy channels. Moreover, a single scalar is poorly suited to descr...

How Hard Is Quantum Advantage? A Cloud Microphysics Stress Test for Variational Quantum Models

Quantum machine learning (QML) could have the potential to leverage advantages of quantum over classical computing but still lacks strong evidence of actual improvements and scalability, partly due to phenomena such as barren plateaus. In this paper, we employ a hybrid quantum neural network (QNN) on a dataset on cloud microphysics, containing processes for phase transitions...

HamQASBench: A Hamiltonian-Informed Diagnostic Benchmark for Evaluating Quantum Architecture Search

Quantum Architecture Search (QAS) automates the design of parameterized quantum circuits for variational quantum algorithms, yet existing benchmarks organize instances by molecular identity or qubit count -- criteria agnostic to Hamiltonian structure -- and rely solely on energy accuracy, which cannot detect structural failures such as over-parameterization on near-product g...

Hidden Gauge Freedom in Complex-Pole Hierarchical Equations of Motion

While complex-pole hierarchical equations of motion (HEOM) have dramatically expanded the reach of numerically exact quantum dynamics simulations of open quantum systems, they suffer from numerical instabilities rooted in the non-Hermitian structure of their Liouvillian. Yet, the origin of this structure remains obscure. Here, we report a previously unknown gauge freedom in...

Mapping open quantum dynamics onto graphs

Graph-theoretic frameworks have been widely employed in quantum physics to address the high-dimensional complexity of quantum systems. Although open quantum dynamics incorporates system-bath coupling via numerous interacting operators, it has been formulated algebraically with a partial set of jump operators or statistically universal reservoirs, leaving the underlying conne...

Breaking the One-Dimensional Expressibility-Trainability Tradeoff

Expressive parameterized quantum circuits (PQCs) are often designed under a dilemma: the growth of expressibility and entangling power (EP) that improves Hilbert-space coverage is also expected to randomize an ansatz and activate barren-plateau (BP) conditions. We show that this dilemma is not a one-dimensional tradeoff. The usual picture collapses three inequivalent objects...

Fast Pulses for High-Fidelity Circularization of Interacting Rydberg atoms

Circular states in Rydberg atoms offer a promising platform for quantum computation, quantum simulation and quantum sensing. However, the final step of their preparation - termed as circularization, a process that involves the transfer of a large amount of angular momentum quanta to the valence electron by means of radio-frequency (RF) pulses - remains as a major bottleneck...

Investigating Role of Electron Correlation Effects via Triple Excitations for Precise Evaluation of Energies and Hyperfine Structure Constants in ^(23)Na

Accurate determination of hyperfine structure constants in atomic systems provides important insight into the interplay of electron correlation and relativistic effects in the nuclear region. Although sodium (Na) is a relatively light atom, previous all-order relativistic many-body calculations of the magnetic dipole hyperfine constants for the low-lying states of ^(23)Na...

Sector-memory obstruction to probe-level bath emergence in finite programmable qubit environments

Finite quantum environments can relax local probes without acting as canonical baths. We study this distinction for a probe qubit coupled to a programmable bath of (N) qubits under excitation-number-conserving dynamics. The conserved charge partitions the Hilbert space into sectors. We characterize probe-level bath emergence using the sector-resolved late-time population (...

MagiQware Secures €575K ($658K USD) Pre-Seed Allocation to Optimize Quantum Magic State Factories via Reinforcement Learning

Delft University of Technology (TU Delft) deep-tech spin-off MagiQware has finalized its pre-seed funding round, reaching a total of €575,000 ($658K USD) in investment capital. Initially launching with a €500K close led by early-stage investment manager LUMO Labs via the TTT.AI programme, the round was expanded to €575K following a subsequent co-investment completion by G...

Heterogeneous Quantum-Classical Workflow Computes Tritium Binding in FLiBe Molten Salts

A research collaboration between Oak Ridge National Laboratory (ORNL), the Cleveland Clinic, and IBM Quantum has completed the first heterogeneous quantum-classical simulation of tritium binding within a liquid inorganic molten salt. Released as a preprint on arXiv by a team including ORNL Section Head Tom Beck, Corporate Research Fellow Al Geist, and Cleveland Clinic sta...

LBNL Researcher Leverages 104 Qubits on IBM Heron to Simulate Subatomic Hadronization

A research collaboration led by the Lawrence Berkeley National Laboratory (LBNL) has successfully simulated hadronization—the fundamental particle physics process where quarks bind via the strong nuclear force to create composite hadrons like protons and neutrons—on a physical quantum processor. Executed by LBNL research scientist Anthony Ciavarella and published in Physi...

Shanghai Expands Quantum Foothold with Xuhui Cultivation Zone and Zhangjiang Quantum Bay Dual Hubs

The municipal government of Shanghai has accelerated its multi-district industrial layout by executing sequential rollouts of two primary quantum infrastructure developments: the newly unveiled "Zhangjiang Quantum Bay" in the Pudong New Area on June 27, 2026, followed by the launch of the Shanghai Quantum Computing Future Industry Incubation Zone in Xuhui District on June...

Who’s News: Strategic Appointments at Silicon Quantum Computing, Pasqal, JIJ, IQM Quantum Computers, IBM, and PostScriptum

Silicon Quantum Computing (SQC) has appointed Karna Nisewaner as Chief Legal Officer, effective June 1, 2026. Nisewaner has over 25 years of legal experience within the semiconductor and artificial intelligence sectors, most recently serving as General Counsel and Corporate Secretary at Cadence Design Systems. Based in Palo Alto, California, she will oversee SQC’s global...

Charge-Sector Construction of the Type-IIB Axion--Dilaton Wormhole Partition Function

I construct the Type-IIB axion--dilaton wormhole partition function from charge-sector data. In a chosen axion charge, equivalently form-field flux sector, the long-distance saddle calculation supplies a two-end operator term with coefficient matrix C^(ij)_ν. The labels i,j label end-insertion operators; the labels A,B label parent universes. Reduction data b...

Coherent Control of Energy Transport at Room Temperature in a Noisy Bath

Coherent control of energy transport in a non-equilibrium steady-state (NESS) in a reaction-center-connected donor-acceptor pair is proposed. The pigments are considered to be continuously interacting with incoherent radiation and a phonon bath while being driven by phase-controlled coherent fields. Coherent excitation of the donor-acceptor pair is shown to induce interferen...

Quantum Spectral Anomaly Detection

A core task in quantum anomaly detection is to compute an anomaly score that quantifies how strongly a test quantum state deviates from a given quantum dataset assumed to be normal. Classically, principal component analysis (PCA) for centered data computes the anomaly score by evaluating the test sample relative to the subspace spanned by the selected leading eigenvectors. H...

Polynomial Initial-State Jumps and Christoffel Transforms in Krylov Complexity

State Krylov, or spread, complexity is a property of a pair (H,ketK_0) rather than of the Hamiltonian alone. Thus, changing the initial state at fixed H generally changes the Lanczos coefficients and the ordered Krylov basis. We solve this relative initial-state problem for normalized polynomial filters, ketψ_Q=Q(H)ketK_0/√N_Q with N_Q=⟨K_0|Q(H)^...

Excitation spectra and rank tomography of linear matrix product tangent spaces

We formulate a tangent-space method for algebraic varieties of matrix product states (MPS) to study excitation spectra of non-uniform quantum many-body systems with open boundary conditions. We further introduce a rank tomography of the MPS tangent space, which characterizes its expressivity in terms of particle-sector rank profiles of the underlying MPS variety. Using the B...

Quasi-holonomy in non-adiabatic quantum evolution

We develop a framework for quasi-holonomy in non-adiabatic quantum time evolution of subspaces along loops in a complex Grassmannian. By factoring the Schrödinger evolution into dynamical and connection-induced contributions in a moving basis, we obtain an effective geometric generator that depends explicitly on the dynamical propagator. This quasi-connection does not define...

Integral representations of f-divergences for general von Neumann algebras

We define and analyze hockeystick divergences and f-divergences for normal positive functionals on general von Neumann algebras, generalizing and unifying previous work in classical probability and finite-dimensional von Neumann algebras. All the main properties of these state distinguishability measures (including in particular monotonicity, convexity, semicontinuity, bou...

Fragile single-cone Dirac quantum walks in two dimensions

It is known that a one-dimensional (1D) quantum walk gives a local space-time discretization of the massless Dirac equation with a single quasi-energy cone (no fermion doubling at low energies), keeping the fundamental symmetries (chiral and time-reversal) of the continuum theory. We show that the analogous 2D construction is fundamentally more fragile. Local two-band quantu...

Characterisation of a satellite-to-ground channel for continuous variable quantum key distribution protocol

In space based quantum key distribution (QKD) protocols, the quantum channel will be dynamic in nature and the channel loss will change with respect to the zenith angle. In the context of continuous variable (CV)-QKD, this will cause issues with parameter estimation and for a transmitted local oscillator in particular it will also fluctuate the shot noise. Therefore, it is v...

Brownian Motion in Orthogonal and Symplectic Groups

Matrix Brownian motion provides a powerful framework for studying crossover ensembles in quantum chaos and quantum transport, as well as thermalization and information scrambling in many-body dynamics. Here, we develop a unified diagrammatic framework to characterize Brownian ensembles for orthogonal and symplectic random matrices, which describe systems with particle-hole s...

Emergent cosmology and gravity from quantum time?

Macroscopic observables allow the recovery of intrinsic dynamics from stationary quantum states. I show that, by interpreting the squared amplitude as the probability density for each definite value of intrinsic time, a curvature emerges in the time direction. For example, from the perspective of intrinsic quantum time, the Friedmann-Lemaître-Robertson-Walker cosmological mo...

Geometric Characteristics of Subproblems in Ising-Machine-Assisted Large Neighborhood Search

Large-scale quadratic unconstrained binary optimization (QUBO) formulations of constrained combinatorial optimization problems often exceed the input-size limit of present Ising machines or suffer from degraded solution quality as the number of binary variables increases. Large neighborhood search (LNS) mitigates this difficulty by sequentially optimizing restricted subprobl...

Quantum Hashing via Constrained Rydberg Many-Body Dynamics

In this Letter, we show that constrained many-body dynamics in Rydberg atom arrays naturally gives rise to a quantum hashing mechanism. By encoding ternary strings into deterministic trajectories in the state space, the classical information space is mapped onto a quantum state ensemble in the Hilbert space with an induced geometric structure. Statistical analysis reveals th...

Extending the Bloch sphere model to an N-qubit system

The Bloch sphere is an elegant tool for representing single-qubit states. However, a widely accepted generalization for multi-qubit systems with entanglement remains absent. We propose a novel geometric model extending the Bloch sphere representation to arbitrary N-qubit systems using 2^N-1 spheres. We demonstrate that any pure 2-qubit state is uniquely described by thre...

Noise-limited secret key agreement with twin optical physically unclonable functions

We investigate the use of twin optical fingerprints derived from correlated physical unclonable functions (PUFs), as a hardware-based platform for cryptographic key generation and distribution. Each fingerprint is associated with a random, yet reproducible speckle pattern, generated when coherent light is scattered by a disordered optical structure. We consider a pair of cor...

Error Mitigation in Bosonic Systems via Virtual Distillation

Virtual distillation is a promising error-mitigation technique that exploits multiple copies of a noisy quantum state to estimate observables as if measured on a purified state. Although originally introduced in the context of bosonic many-body systems under the name of virtual cooling, its development and applications have largely focused on qubit-based quantum computation....

Quantum orientation, Noether structure, composition of systems and operations

In this paper we argue that, in addition to the statistical structure of quantum theory, another structure, referred to here as the ``Noether structure," is necessary to describe the composition of systems and to define completely positive operations. A Noether structure reflects the dual role of Hermitian operators as observables on the one hand and as generators of symmetr...

A Unified Electrostatic-to-Spin Framework for Asymmetric Multi-Gate CMOS Quantum Devices

In advanced complementary metal-oxide-semiconductor (CMOS) quantum chips, compact gate stacks make it difficult to connect lithographic geometry, electrostatic confinement and many-electron spin filling in one transparent model. This connection is central to design-technology co-optimization (DTCO). Here we develop a reduced-order analytical framework for asymmetric multigat...

Emergence of the Scrooge Ensemble in the Sachdev-Ye-Kitaev Model

The probabilistic nature of quantum measurement provides a direct window into the structure and complexity of many-body wave functions. When only part of a system is measured, the remaining degrees of freedom form an ensemble of post-measurement states whose statistical structure can reveal a stronger form of thermalization, known as deep thermalization. Recent numerical evi...

Strain- and potential-controlled tunneling in monolayer MoS_2

We present a theoretical study of spin- and valley-resolved quantum transport in monolayer MoS_2 under the combined influence of mechanical strain and an external scalar potential, a combination whose simultaneous unexplored. Within an effective massive Dirac Hamiltonian that incorporates intrinsic spin--orbit coupling, strain induces valley-dependent momentum shifts that...

Magnetic graphs for cavity quantum electrodynamics

Strengthening light-matter coupling has become a central challenge in cavity quantum electrodynamics (QED), enabling ultrafast gate operations, qubit protection, and deterministic nonlinear optics. As the coupling increases, even the simplest configuration, a two-level atom interacting with a quantized field, requires careful treatment, as exemplified by the gauge-invariant...

All-optical control of coherent perfect absorption via frequency conversion

Coherent perfect absorption (CPA) extinguishes optical fields through interference and dissipation, but conventional implementations rely on material loss that is largely fixed after fabrication. Here we demonstrate all-optically controllable CPA based on frequency conversion in a periodically poled lithium niobate waveguide resonator. Pump-driven frequency conversion couple...

Estimation of a sparse multi-qubit Hamiltonian via compressed sensing

Hamiltonian estimation is an effective approach in studying the structure and dynamical evolution of quantum systems. The difficulty in estimating the Hamiltonian is that an N-qubit Hamiltonian has 4^N-1 unknown parameters, requiring exponentially many equations for information extraction. In this paper we develop a method based on compressed sensing to estimate the Hami...

Krylov complexity, mode-resolved complexity and entanglement entropy across phase transitions in the non-Hermitian extended Su-Schrieffer-Heeger model

We investigate phase transitions in the extended Su-Schrieffer-Heeger (SSH) model with next-nearest-neighbor hoppings and an imaginary staggered chemical potential. In the presence of small non-Hermiticity, exceptional points emerge in pairs from the gap-closing momenta near the topological phase boundaries of the Hermitian limit. Utilizing the Krylov spread complexity and e...

QuTuner: Feature- and Learning-Guided Optimization Pass Tuning for Quantum Compilers

Quantum compilers play a key role in transforming quantum circuits into lower-cost implementations with improved execution fidelity. This process is commonly guided by circuit-level metrics, such as gate counts and circuit depth. Although compiler pass tuning has been widely studied in classical compilation, directly transferring these techniques to quantum compilers is chal...

Quantum random walks on d-regular graphs with Haar-random coin operators

With unitary coin operator that is a random matrix drawn from a uniform distribution with respect to the Haar measure, we construct a variant of a discrete quantum random walk using a d-regular undirected connected simple graph. With each step of the walk, the coin operator random matrix is drawn independently from the distribution. The expectation value over the distributio...

Equiangular weighted frames and conical 2-designs with unequal traces

Conical 2-designs are families of positive operators possessing crucial symmetry properties that allow them to efficiently characterize important quantum measures. However, little is known about their general structures and properties. We propose a construction method of conical 2-designs whose elements are not of equal traces, based on a generalization of equiangular weight...

Security of Quantum Conference Key Agreement with Two-Way Classical Communication

Quantum conference key agreement (QCKA) enables multiple users to establish a common secret key with information-theoretic security and is regarded as a key primitive for secure communication in future quantum networks. However, practical implementations of QCKA typically suffer from higher noise levels than conventional bipartite quantum key distribution (QKD), making the i...

White House to Convene Quantum Industry Summit as Administration Pushes Innovation Agenda

EigenQ Announces Post-Quantum Security Integration for Intel Xeon Systems

Keyfactor Announces $1B+ Strategic Growth Investment to Expand Leadership in Securing Post-Quantum Enterprise

Hybrid Quantum Algorithm Improves Portfolio Optimization on Trapped-Ion Quantum Computer