June 10, 2026

Coset Ensemble Decoder for Quantum Error Correction with Algorithm-Hardware Co-Design

Reliable large-scale quantum computation relies on fault-tolerant architectures, where quantum error correction (QEC) continuously extracts and decodes error syndromes in real time. A critical component in QEC is the decoder, a classical subsystem that must simultaneously deliver high logical accuracy and ultra-low latency. This paper presents a novel algorithm-hardware co-d...

On pseudogap phase as precursor to a superconducting dome in high-Tc cuprates: Non-analytic T* as a function of doping

We generalize the condition under which a quantum material exhibiting a pseudogap phase is a precursor to a superconducting (SC) dome. The result reveals the non-analytic T* as a function of doping. A well-known example is the high-Tc cuprates. Essentially, the SC dome is generated under two conditions: (1) that the pseudogap T* is a decreasing function of doping, due to the...

Bosonic Cyclic Codes: Trading Stabilizers for Gaussian Non-Clifford Phase Gates

Bosonic codes offer hardware-efficient approaches to quantum error correction, with the best encodings offering effective protection of idle quantum information against loss and dephasing - particularly rotation-symmetric codes, which include the cat and binomial code families. However, rotation-symmetric codes are only naturally endowed with a single logical Pauli gate, whi...

Analog Quantum Asynchronous Event-Based Graph Neural Network

Asynchronous, event-based graph neural networks (AEGNNs) have recently emerged as an efficient paradigm for processing the sparse and high-temporal-resolution data from event cameras. In this paper, we propose quantum analog AEGNNs (QA-AEGNNs), a novel framework to implement an AEGNN on a neutral-atom quantum computer. Neutral-atom quantum processors offer a programmable ana...

Inherent flux crosstalk and coupler-driven single-qubit gates in superconducting circuits

Crosstalk refers to unwanted qubit addressing. This is particularly detrimental when scaling up quantum information systems because unintended interactions limit their overall performance. For superconducting qubits, tunable couplings and frequency tunability achieved through externally applied magnetic fluxes enable high-fidelity entangling gates; however, they also introdu...

Unitary Channel Testing Under a Depolarizing Noise Assumption

We present fast algorithms unicodex2013 under the depolarizing noise assumption, often made in fault-tolerant quantum computations unicodex2013 to test its strength. Our optimal algorithms answer the following question: is the quantum channel implemented by a given black box identical to a target unitary or ε-far from it in the diamond distance, assumin...

Ultra-high Q-factor superconducting tantalum resonators on 300 mm Si wafers

Superconducting resonators are central to superconducting quantum information technologies and essential for bosonic qubit architectures, where long-lived storage modes enable hardware-efficient error correction. Achieving ultra-high quality factors in scalable planar circuits is challenging because multiple dissipation channels contribute to the total loss. Here we report p...

Non-Hermitian scattering in SSH superconducting waveguides: exact Green-function reduction and dimerization-sensitive microwave functionalities

We formulate an exact Green-function theory for non-Hermitian single-microwave-photon scattering by finite superconducting circuit subsystems embedded in an SSH waveguide. The structured SSH environment is integrated out exactly and enters the local scattering problem as an energy-dependent matrix self-energy, reducing the full open system to a finite-dimensional effective n...

The Yang-Baxter Equation for the Chiral Potts Model and Integrable Parafermions

A new type of Yang-Baxter equation (YBE) for R-matrices parameterized by three spectral parameters is constructed from the star-triangle and star-star relations for the chiral Potts model. As the Z_N symmetric generalization to the Ising model, its Boltzmann weights are known to depend on two variables describing a curve with genus larger than one for N>2, except for t...

Experimental implementation of continuous-variable QAOA on a quad-rail lattice cluster state

We experimentally demonstrate the continuous-variable quantum approximate optimization algorithm (CV-QAOA) for multi-variable problems and multiple QAOA depths using a measurement-based CV quantum computing platform on a quad-rail lattice (QRL) cluster state. We propose a systematic method to map arbitrary quadratic cost functions onto the QRL architecture and examine the re...

Neural-network solution of subtracted three-body Faddeev integral equations near the Efimov limit

We apply a deep-neural-network (DNN) ansatz to the symmetrized spectator vector of the subtracted three-body Faddeev integral equation for identical bosons near the Efimov limit. The network is trained by minimizing the residual of the discretized integral equation, while the positive binding scale associated with the three-body energy is treated as a trainable parameter. De...

Trainability of IQP Quantum Circuit Born Machines Under Gaussian Initialization

Quantum Circuit Born Machines (QCBMs) offer a natural approach to generative machine learning by leveraging the Born rule. Recent work has provided a method to classically train QCBMs with Instantaneous Quantum Polynomial (IQP) circuits via the Maximum Mean Discrepancy (MMD) loss. Despite the assumed intractability of sampling from IQP circuits classically, their expectation...

Towards the implementation of a quantum classifier

In this work, we investigate the use of a quantum circuit as a binary classification model in the context of quantum machine learning. We call this model, binary quantum classifier. First, we describe fundamental concepts of quantum computing and introduce the computational tool used: Qibo, an open-source framework for efficient quantum simulations and quantum hardware contr...

VQA for Dynamic Portfolio Optimization: Sampling Strategies, Optimizer Scheduling, and Hardware-Aware Ansatz Design

Variational quantum algorithms are increasingly explored for optimization problems at scales relevant to near-term quantum devices. Their practical performance depends strongly on design choices such as the sampling objective, classical optimizer, and ansatz layout before and after hardware transpilation. We study these factors for dynamic portfolio optimization, a multi-per...

Floquet analysis of coherence in periodically driven diamond NV ensemble systems

High-density nitrogen-vacancy (NV) ensembles are promising platforms for solid-state quantum sensing, but their performance is limited by dipolar interactions and inhomogeneous dephasing. Periodic decoupling sequences such as Waugh-Huber-Haeberlen (WAHUHA) can extend the observed stroboscopic decay time. However, it remains unclear that a longer effective dephasing time yiel...

Keyfactor Launches Trust Control Plane to Unify Digital Trust Across the Enterprise

ZenaTech Included in Russell 3000 Benchmark Index

ELECTRA AI and Naoris Quantum Protocol Partner on Quantum-Safe Battery Intelligence

Quantum statistics in an extended collider coupled to a qubit

Mesoscopic colliders provide an effective platform for probing the mutual statistics of quantum particles. Recent experiments have successfully extracted the mutual statistics of fermions, and more exotic anyons using quantum point contacts (QPCs). Coupling a point-like collider, such as a quantum point contact, to a two-level impurity or qubit can induce statistical transmu...

Interplay between photon condensation and electron-electron interactions in molecular systems

We investigate a minimal molecular model consisting of square planar plaquettes hosting multiple electrons, whose dynamics is governed by a tight-binding Hamiltonian supplemented by on-site Hubbard repulsion. By coupling this system to a spatially nonuniform cavity mode, we analyze the emergence of a magnetostatic instability, namely photon condensation, originating from the...

Colloquium: Nuclear clocks

The Th-229 nuclear isomeric state has the lowest energy of all known nuclear excited states, placing it within the reach of current table-top laser technology. This extraordinary property has made this nuclear isomer an attractive candidate for a nuclear optical clock of incredibly high precision and accuracy, both as isolated trapped Th-229 ions and embedded into solid-stat...

Revealing the topology of quantum states via Kirkwood-Dirac quasiprobabilities

We discuss a theoretical approach to discriminate whether two states of a many-body quantum system belong or not to different topology classes. This approach is based on expressing a strange correlator - a recently established tool for quantum topology discrimination - between the states as a function of Kirkwood-Dirac quasiprobabilities (KDQs). KDQs provide a first-principl...

Adaptive identification of low-degree polynomials in quantum singular value transformation: application to nonlinear quantum properties estimation

Estimating properties of unknown quantum states via quantum singular value transformation (QSVT) often requires high-degree polynomials to handle small eigenvalues of density matrices. Specifically, the existing approaches determine the polynomial degree by relying on overly conservative worst-case bounds based on the minimum non-zero eigenvalue or the rank of the density ma...

Nonreciprocal quantum rotation sensing via virtual-excitation enhancement in a spinning cavity

Quantum sensing with high precision and sensitivity plays an important role in quantum technologies and quantum information processing. Here, we propose a nonreciprocal quantum metrological scheme for estimating rotational angular velocity in a hybrid light-matter platform, where the setup consists of a spinning ring cavity coupled to a two-level system and an auxiliary boso...

Robust self-testing based on Gisin's arbitrary-input Bell inequality

Self-testing refers to the strongest device-independent (DI) certification method that validates the nature of a quantum system and devices solely based on the observed statistics. We demonstrate the self-testing of state and measurements based on the Gisin Bell inequality (GBI) featuring arbitrary inputs for both parties. We introduce a systematic and elegant sum-of-squares...

Random Matrix Theory for Chaotic Wave Scattering and Transport

We review random matrix approaches to chaotic wave scattering and transport in open systems. Starting from the effective non-Hermitian Hamiltonian formulation, we discuss the scattering matrix, reaction matrix, time delays, and complex resonances as complementary probes of open chaotic dynamics. We emphasize universal statistics governed by symmetry, openness, and channel co...

Genuine Multipartite Nonlocality for Arbitrary Input: Maximal Randomness Generation and Robust Self-Testing

Bell nonlocality provides the foundation for device-independent (DI) certification of quantum devices. We introduce a Bell inequality capable of identifying genuine multipartite nonlocality (GMNL) in an arbitrary m-partite scenario with an arbitrary odd number of measurements per party. Since the multi-setting nature of this inequality precludes the use of Jordan's Lemma, we...

Schmidt Decomposition-Based Methods for Efficient Quantum Image Encoding

In quantum image processing, a fundamental step is encoding classical image data into quantum states. This can be achieved using methods such as Flexible Representation of Quantum Images (FRQI), Quantum Probability Image Encoding (QPIE), and Novel Enhanced Quantum Representation (NEQR). However, on real quantum hardware, these encodings can quickly lead to circuits with many...

Quantum Colorings of Spheres

Cameron, Montanaro, Newman, Severini and Winter gave a construction which shows that, for n ∈{2,4,8}, any graph G which admits a real n-dimensional orthogonal representation is quantumly n-colorable. This result can be recast as the statement that the real sphere S^(n-1) is quantumly n-colorable for these values of n. We investigate possible extensions of...

Sensitivity Enhancement near High-Order Exceptional Points via Dissipative Couplings

High-order exceptional points (EPs) emerging in non-Hermitian systems have attracted broad interest for their significantly enhanced sensitivity to perturbations. However, quantum sensing schemes based on high-order EPs remain scarce, due to the experimental challenge of fine-tuning the system to such an extremely sensitive isolated point. Here we propose a four-channel diss...

The fidelity of controlled quantum teleportation in a noisy environment

In this work, we investigate controlled quantum teleportation in the presence of noisy channels acting on the three-qubit resource state. We employ a series of generalized noisy channels that bridge the dephasing channels and amplitude damping channels while encompassing extensive intermediate scenarios. We provide an in-depth analysis of the degradation of the maximal avera...

Pair creation amplitudes for a real scalar field coupled to a time-dependent surface in d+1 dimensions

We study the pair creation phenomenon for a real scalar field φ in the presence of a surface that undergoes time-dependent deformations, while imposing Dirichlet-like boundary conditions. Including terms up to fourth order in the departure of the surface from an infinite plane, we present results for the angular dependence of the emission rate for the vacuum-to-pair...

Noise cancellation by superposition of channels and superactivation of quantum capacity: Experimental realization by NMR

Noisy quantum channels degrade quantum resources such as coherence and entanglement and hence pose challenges for realizing quantum technologies. Coherent control of noisy channels allows us to minimize their effects on the quantum system. Here we achieve the cancellation of two noisy quantum channels by superposing their corresponding Stinespring dilation unitaries. We firs...

Certification of Network Quantum Sensing

The distribution of quantum sensors on quantum networks is a key enabler of quantum technologies in interferometry, gravimetry, timekeeping, biological monitoring, and beyond. Yet, guaranteeing the security of these distributed sensors over noisy, insecure networks remains a formidable challenge. Previous efforts to combine quantum metrology and cryptography have encountered...

Equilibrating continuous-variable open quantum systems using stochastic classical trajectories in path-integral space

Beyond the weak-coupling limit, open quantum systems equilibrate to a highly entangled thermal state. For continuous-variable systems, this state can be written explicitly as an imaginary-time phase-space path integral, in which the positions are directly entangled with the bath, and the momenta are correlated with the positions through a phase term. Here, we ask to what ext...

Hawking-Page phase transition for pure Lovelock black holes

We investigate the thermodynamic properties of static, spherically symmetric Anti-de Sitter (AdS) black holes, focusing on the interplay between characteristic temperatures, as well as on the universality of Ruppeiner scalar curvature at the Hawking-Page (HP) phase transition. In particular, we study the relation between the minimum temperature and the HP phase transition te...

Anomalous mobility edges and extended-localized transition in a quasiperiodic emitter-cavity array

The manipulation of localization in quasiperiodic systems by mobility edges or localization transition holds significant physical importance. In this letter, we demonstrated that the dissipation can induce the emergence of anomalous mobility edges and extended-localized transition in emitter-cavity arrays controlled by quasiperiodic potentials. Specifically, we observe that...

Interaction-driven dynamics in graphene flakes as a benchmark for quantum simulation

We study interaction-driven ultrafast dynamics in finite graphene flakes following an optical pump quench in an interacting tight-binding model. By comparing exact real-time evolution with simulations restricted to particle-hole excitation subspaces, we assess when relaxation can be captured by low-order many-body processes and when this is not sufficient. The single-particl...

Precision measurements at the interface between unitary and non-unitary encoding

We investigate precision scaling at the interface between unitary and non-unitary encoding under generalized noise including single-particle and collective dephasing and decay. Using linear response theory and the error propagation formula, we derive analytic precision expressions for both the unitary parameter Ω and the dissipation strength γ. For unitary encoding, when...

Analytical performance evaluation of quantum radar architectures: From single-photon to entangled-noise radars

This article presents a comprehensive analysis of two classes of quantum radars, including quantum direct-detection and quantum-entangled noise radars. In the first case, inspired by the well-established concept of single-photon LiDARs, we investigated the performance of single-photon radars, in which state-of-the-art single microwave-photon detectors are employed to enhance...

Optomechanical system with tunable dissipative and dispersive couplings

We demonstrate an optomechanical system with tunable dissipative and dispersive couplings using a Fabry-Perot cavity and a string mechanical resonator. By varying the diameter and material of the mechanical resonator, and the relative location between the mechanical resonator and the cavity, the relative strengths of dissipative and dispersive coupling could be tuned continu...

Reconfigurable MDI-QKD and BB84 over 20 km optical channels via EOM-tailored weak coherent states

Measurement-device-independent quantum key distribution (MDI-QKD) is designed to eliminate detector side-channel vulnerabilities. However, its practical deployment remains experimentally demanding because it requires two-photon interference (TPI) between mutually phase-randomized optical states. In this study, we demonstrate a reconfigurable platform that supports both polar...

A Recrossing-Free Dividing Surface in Quantum Mechanics

For nearly a century, a recrossing-free dividing surface in quantum mechanics has been thought impossible. One-way reactive flux seems to require simultaneous trajectory-level knowledge of position and momentum -- an apparent conflict with the uncertainty principle. We show that this obstruction is not fundamental. The exact quantum flow can admit stable and unstable invaria...

Identical Bosons, large occupation numbers and classical field description

For a system with a large number of identical Bosons, it is common to claim, often without any additional justifications, that, when the mean occupation number in a single particle state is sufficiently large, classical field description will be applicable. This is why e.g. for ultra-light dark matter, the classical field equations are used to compute its dynamics. In this w...

Scaling law of asymptotic freedom in collective charging of quantum batteries

We establish a universal scaling law for collective charging of quantum batteries, independent of microscopic details. We prove that the ergotropy-to-energy ratio approaches unity at least as fast as ~N^(-1) with the number of batteries N, implying generic asymptotic freedom. We further show how the universal 1/N scaling can be overcome: when the battery state beco...

ICQIA Expands Global Reach With New Charter And Members

Quantum Sensor Advance Could Transform Army Battlefield Signal Detection

Estonia Upgrades National Digital Identity Cards with Thales

QTREX Awarded Government Grant to Advance Native RF Dielectric Material for Quantum Computing