May 19, 2026

Universal Jaynes-Cummings Control of an Oscillator

The Jaynes-Cummings (JC) interaction-the coherent exchange of excitations between a two-level system and a harmonic oscillator-is one of the fundamental interactions of quantum optics, realized across platforms such as cavity quantum electrodynamics, trapped ions, mechanical resonators, and superconducting circuits. Although JC interactions and qubit rotations form a univers...

Realization of waveguide many-body quantum optics

Controlling light photon-by-photon is central to quantum optics. At a fundamental level, photon interactions are mediated by their coupling to atoms, and ultimate control requires deterministic light-matter interfacing of single photons to single atoms. Extending this paradigm to radiatively couple multiple individual atoms in a deterministic and scalable manner opens the ar...

Quantum magic of strongly correlated fermions - the Hubbard dimer

We study the non-stabilizerness (quantum magic) content of the Hubbard dimer, an analytically solvable, yet completely non-trivial, model of strongly correlated fermions. We can access zero- and finite-temperature properties as well as the time evolution in a quantum quench protocol. We evaluate local and nonlocal non-stabilizerness using both the robustness of magic and the...

Topologically protected long-range correlations in steady states of driven-dissipative bosonic chains

Driven-dissipative quantum systems can exhibit robust transport and amplification in topological regimes, yet the connection between topology and the extent of correlations remains largely unexplored. In this work, we develop a general framework that links topological phases in driven-dissipative systems to bosonic correlations via the singular value decomposition (SVD). In...

Precision limits for time-dependent quantum metrology under Markovian noise

We derive ultimate precision bounds for estimating parameters encoded in \emph{time-dependent} Hamiltonians in the presence of general Markovian noise, allowing for arbitrary adaptive protocols with fast controls and noiseless ancillas. Extending the minimization-over-purifications framework to time-varying continuous channels, we obtain a differential upper bound on the ach...

Reduced-State Stabilizer Rényi Entropy as a Probe of Quantum Criticality in the Transverse ANNNI Model and the Quantum Compass Model

We investigate the effectiveness of the stabilizer Rényi entropy (SRE), a quantifier associated with non-stabilizer resources (quantum magic), as an indicator of quantum phase transitions. Specifically, we analyze the behavior of the purity-corrected SRE of reduced density matrices in the ground states of two one-dimensional spin models: the transverse axial next-nearest-nei...

Dissipation-assisted preparation of Floquet-Laughlin states in superconducting circuits

Fractional Chern insulators (FCIs) are lattice analogs of fractional quantum Hall systems, where the interplay of strong interactions with a frustrated tunnelling kinetics leads to the emergence of a gapped ground state with long-range entanglement and anyonic excitations. The highly correlated nature of such systems makes their adiabatic preparation challenging already beyo...

Phonon-bottlenecked spin relaxation of Er^(3+):CaWO_4 at milliKelvin temperatures

We study spin-lattice relaxation times of electron spins in Er^(3+):CaWO_4 at millikelvin temperature, detected via their coupling to a low-mode volume superconducting resonator. At large magnetic field supporting strong phonon-emission rates, we observe a noticeable increase in relaxation times with increasing spin-excitations, which exhibit a unique [tanh(ℏω_0/...

Can machine learning for quantum-gas experiments be explainable?

Virtually all aspects of many-body atomic physics are challenging: experiments are technically demanding, datasets have become enormous, and the memory and CPU requirements for classical simulation of generic quantum systems often scale exponentially with system size. Machine learning (ML) methods are already assisting in each of these areas and are poised to become transfor...

Reinforcement Learning Assisted Quantum Simulation of Many-Body Excited States and Real-Time Dynamics

The computation of electronic excited states and real-time quantum dynamics of many-fermion systems is among the most promising applications of near-term quantum computing. In this work, we generalize the reinforcement learning contracted quantum eigensolver (RL-CQE), previously developed for ground-state problems, to electronic excited states and real-time quantum dynamics,...

Discovering Data Encoding Strategies for Quantum-Classical Neural Networks Using Monte Carlo Tree Search

Quantum machine learning (QML) has attracted considerable research interest, yet whether it offers practical benefits over classical approaches remains an open question. The choice of data encoding significantly influences QML performance, but why certain encodings outperform others remains poorly understood. We employ Monte Carlo Tree Search (MCTS) to discover optimal data...

The QuaST Decision Tree: Achieving Automation With Data-Based Recommendations

Quantum computers are increasingly powerful. Software tools for the development of quantum-enhanced algorithms are maturing. However, the software stack still lacks the connection to applications that would enable hybrid algorithms combining classical and quantum computing steps. End users need to be assisted in choosing the best combination of preprocessing, postprocessing,...

Hybrid Quantum-Classical Neural Architecture Search

Hybrid quantum-classical neural networks (HQNNs) are emerging as a practical approach for quantum machine learning in the noisy intermediate-scale quantum (NISQ) era, as they combine classical learning components with parameterized quantum circuits in an end-to-end trainable framework. However, their performance and efficiency depend strongly on architectural choices such as...

QLIF-CAST: Quantum Leaky-Integrate-and-Fire for Time-Series Weather Forecasting

Accurate and efficient time-series forecasting remains a challenging problem for both classical and quantum neural architectures, particularly in multivariate environmental settings. This work adapts the Quantum Leaky Integrate-and-Fire (QLIF) spiking neural network for time-series regression tasks, specifically short-term multivariate weather forecasting. We extend QLIF bey...

Regularized Counterdiabatic Driving for the Quantum Rabi Model

Counter-diabatic (CD) driving provides a powerful route to fast and robust state preparation by suppressing diabatic excitations during finite-time evolution. Yet, deriving analytical CD protocols for complex systems remains challenging, motivating the development of variational approaches. These methods typically rely on minimizing trace-based functionals to construct appro...

Parameterized 4-Qubit EWL Quantum Game Circuits with Dirac-Solow-Swan Hamiltonian Integration for Quadruple Helix Disruptive Innovation Recommender Systems

We present a novel parameterized 4-qubit Eisert-Wilkens-Lewenstein (EWL) quantum game circuit for recommender systems in quadruple helix innovation ecosystems (academia, industry, government, and civil society). The local strategy operators U_i = R_y(θ_i) for each helix actor are directly tuned by normalized dominance weights extracted from real participant funding dat...

Quantum Emitters at Telecommunication Wavelengths based on Carbon Defects in Transition Metal Dichalcogenides

Low-dimensional materials have emerged as promising hosts for quantum emitters, whose emission typically arises from either strain-induced band bending or defect-induced two-level systems. Among these materials, transition metal dichalcogenide (TMD) monolayers have attracted particular attention; however, their performance is limited by strong photoluminescence (PL) quenchin...

Confinement-controlled pattern selection in a finite population-imbalanced dipolar Bose-Einstein condensate

We study the ground-state density patterns of a population-imbalanced two-component dipolar Bose-Einstein condensate confined in a circular quasi-two-dimensional box. Using a mean-field model, we map out phase diagrams as functions of the axial confinement, interaction imbalance, and population ratio. The system supports a rich sequence of stationary morphologies, including...

Aramco And Pasqal Launch Saudi Arabia’s First Quantum Computer And Middle East’s First Commercial QCaaS Platform

Illinois Wesleyan to Launch Interdisciplinary Undergraduate Quantum Science and Engineering Program

Quantum Shannon theory made robust: a tale of three protocols for almost i.i.d. sources

The asymptotic rates of information-theoretic protocols - including error exponents, compression rates, and channel capacities - are traditionally defined under the idealised assumption that the underlying resource (state or channel) is independent and identically distributed (i.i.d.). Somewhat surprisingly, even slight departures from the exact i.i.d. structure can lead to...

Detecting nonclassicality in randomly-displaced copies of a squeezed state

We address a fundamental question: Can one determine whether a received signal is squeezed when each copy arrives with a different displacement/amplitude? We introduce an interaction Hamiltonian that converts quadrature squeezing into number squeezing. Using this conversion, we test whether the copies satisfy g^((2))(0)<1. The Hamiltonian itself does not create nonclassica...

Strategy optimization for quantum conference key agreement in asymmetric star networks

The distribution of entangled states is a core task for quantum networks facilitating quantum communication, and the use of multipartite entangled states comes with its own set of considerations. In this work, we analyze a quantum conference agreement protocol based on GHZ states in a network with a central station to which multiple clients are connected. Using comprehensive...

Modular Lower Bounds on Reeh-Schlieder State Preparation

The Reeh-Schlieder theorem says that every target vector can be approximated from the vacuum by an operator localized in an arbitrarily small spacetime region, but it gives no quantitative cost for doing so. This note isolates a standard Tomita-Takesaki estimate as a model-independent preparation bound. Targets with deeply negative modular energy require large local operator...

Open quantum dynamics without Complete Positivity: a criticism

The requirement of complete positivity is very often regarded as a fundamental consistency condition for the description of open quantum dynamics. We critically examine this requirement and discuss both its physical motivations and its limitations. We analyze proposals based on restricting the domain of non-completely positive maps to subsets of compatible initial states. Us...

Fibonacci many-body scars in a decorated Rule-54 quantum cellular automaton

Quantum many-body scars provide a controlled form of weak ergodicity breaking, in which structured nonthermal eigenstates coexist with a thermalizing many-body spectrum. We introduce a qubit-level route to exact scars based on the intrinsic soliton structure of the Rule-54 quantum cellular automaton. A hard-core dimer sector of Rule 54 supplies an exactly translatable protec...

Non-Gaussian Entanglement Hierarchy Based on the Schmidt Number

Non-Gaussian entanglement is a promising resource in various quantum tasks. A recently defined class identifies entanglement that cannot be generated by applying Gaussian operations to separable inputs. To further explore the entanglement in this context, we introduce a quantitative witness E_(rmNG) in bipartite bosonic systems, which satisfies E_(rmNG)=1 for all Gau...

Krylov complexity and fidelity susceptibility in two-band Hamiltonians

We investigate Krylov spread complexity for the ground state of two-band Hamiltonians, where the reference state is a generic state on the Bloch sphere. The spread complexity is obtained by using a purely geometric formulation in terms of Bloch sphere data without constructing the circuit Hamiltonian. For generic reference states, the derivative of the spread complexity is l...

Scalar-Tensor Gravity as a Probe of Generalized Black Hole Entropy

We develop a geometric realization of a broad class of generalized black hole entropy functionals by establishing their direct correspondence with the Misner-Sharp quasilocal mass and the Wald Noether-charge entropy in scalar-tensor theories of gravity. The resulting models feature a scale-dependent effective gravitational coupling, whose functional dependence is deter...

A geometric Fano--Procrustes framework for purification-based distances and quantum channels analysis

In this work we reformulate the Uhlmann purification-overlap optimization and develop a purification-based geometric framework for the analysis of mixed qubit states and qubit channels. Using the Fano representation of two-qubit pure states, a purification is described in terms of the Bloch vector of the system, the ancilla Bloch vector, and a real correlation matrix. For a...

Geometrical derivation of Wigner's angle for arbitrary Lorentz transformations of massless particles

This note summarizes the physics and mathematics of Lorentz transformations for massless particles, specifically for photons. We provide a complete analytical derivation of Wigner's little group matrix and a closed formula for the calculation of Wigner's angle for arbitrary Lorentz transformations. Our derivation highlights the geometrical content of the sequence of little g...

Bounds on quantum conference key agreement in pair-entangled networks

We investigate the task of conference key agreement in near-term quantum networks, where the nodes are connected by sources of bipartite entangled states, under the class of local operations not requiring quantum memory. We derive upper bounds on the distillable conference key depending on the network topology and degree of entanglement of the sources, and prove tightness of...

Quantum Model for CVRPTW

This paper proposes a quantum algorithm for the capacitated vehicle routing problem with time windows (CVRPTW) based on Grover Search framework. This problem is often faced by Postal services in the context of package delivery or other time-sensitive operations. We provide an implementation on gate based quantum computer of a model inspired by classical route first, cluster...

Zeno-Assisted Quantum Heat Engines

Finite-time quantum heat engines (QHEs) typically extract less work than their quasistatic counterparts because fast driving generates coherences and non-adiabatic transitions during the work strokes, a phenomenon commonly referred to as quantum friction. Quantum lubrication denotes a broad class of strategies that use auxiliary systems or controls to mitigate this loss. In...

Quantum randomness beyond projective measurements

The unpredictability of quantum physics gives rise to intrinsic randomness. In an adversarial scenario, any additional degrees of freedom must be attributed to an eavesdropper with correlations to the measurement set-up. The true randomness is then quantified by the probability that she correctly guesses the measurement outcomes, optimised over all possible strategies. Extre...

Strong nanomechanical Duffing nonlinearity and interactions induced through cavity optomechanics

Nonlinearity is a key resource in both classical and quantum signal processing. Nonlinear nanomechanical elements have found applications ranging from sensing to computing, while networks of nonlinear resonators, as well as nonlinearly coupled networks of linear resonators, constitute promising platforms for simulating complex dynamics. Here, we experimentally demonstrate an...

Energy-Resolved Eigenmode Spectroscopy of 1-D and 2-D Non-Hermitian Skin Effects

Non-Hermitian lattices can host the non-Hermitian skin effect, a boundary-induced collapse of all bulk eigenstates into exponentially localized edge modes. This effect underlies anomalous bulk-boundary correspondence and remarkable enhancements in non-Hermitian sensing, yet direct energy-resolved access to the eigenmodes of non-Hermitian lattices has remained limited. Here w...

Quantum--Fluid Correspondence for Systems of Nonrelativistic Spin-1/2 Particles

We show that a charged fluid endowed with an internal spin degree of freedom naturally satisfies the Pauli equation for a nonrelativistic spin-1/2 particle, and that a collection of n such interacting fluids can be reformulated as an Euler flow in 3n dimensions, thereby providing a natural representation of a system of n Pauli particles. These results provide a fluid-mechani...

One pure steered state implies Einstein-Podolsky-Rosen steering

In this work, we show that a two-qubit entangled state admitting at least one pure steered state is Einstein-Podolsky-Rosen (EPR) steerable from Alice to Bob. Pure steered states signifies that the quantum steering ellipsoid of Bob is tangent to his Bloch sphere at least at a single point. Furthermore, we prove that for a two-qubit entangled state, Bob's quantum steering ell...

An Entropy-Governed Speedup for Quantum Algorithms on Local Hamiltonians

Low-energy estimation and state preparation for general k-local Hamiltonians are fundamental challenges in quantum complexity theory. For constant relative accuracy, Buhrman et al. (PRL 2025) recently broke the natural Grover bound O(2^(n/2)), where n denotes the number of qubits, for both problems. In this paper, for any sufficiently small parameter d≥0, we prese...

Positivity of the effective range for finite range attractive potentials with a repulsive core

In the phenomenological study of exotic hadrons, the sign of the effective range, r_0, is invoked as a criterion to distinguish between compact multiquark configurations (associated with r_0 < 0) and loosely bound hadronic molecules (r_0 > 0). Motivated by this, we investigate the fundamental constraints on the sign of the effective range for single-channel local inter...

Integrated time-bin entangled quantum light source on a 4H-SiC microring chip

Integrated time-bin-entangled photon-pair source with cavity-enhanced nonlinear optical processes is essential for quantum information technologies. However, microcavities with a high quality factor inherently introduce a trade-off between generation efficiency and photon bandwidth, which hinders the development of high-speed quantum networks with an integrated source. Here,...

Linear-optical test of quantum contextuality with sequential measurements

Quantum contextuality provides a fundamental signature of nonclassical behavior that cannot be explained by noncontextual hidden-variable models. We propose and experimentally implement a linear-optical setup for demonstrating Kochen-Specker contextuality via a violation of the KCBS inequality using single photons. Our scheme employs sequential measurements realized with lin...

Shortcut-error signatures in coherence-retaining endpoint work quasistatistics

Quantum work statistics differ from classical ones because initial energy coherence matters. The standard two-point measurement (TPM) gives a positive distribution but erases phase information. Coherence-retaining endpoint-work quasistatistics provide a compact probe of shortcut-to-adiabaticity performance. For work defined with respect to a reference Hamiltonian, an exact c...

Quantum signatures and semiclassical limitations in the transmission of Fock states

Transmission through potential barriers is a fundamental problem in quantum mechanics. While semiclassical methods can approximate certain aspects of transmission, they fail to capture the intrinsically quantum interference associated with Wigner-function negativity. We numerically study the transmission of displaced Fock states through an inverted-oscillator barrier, with a...

Thales Alenia Space Announces Successful High-Precision Quantum Transmission Between The Canary Islands of LaPalma And Tenerife

Sydney Quantum Academy Expands Quantum Industry Experience Program

Clemson University Advances Quantum Software Research Through $650,000 Initiative Focused on Real-World Hardware Performance

The Good, The Bad and The Buggy: G7 Paper Outlines Promises and Threats of Quantum Tech for the Financial System

Sygaldry Raises $139 Million to Build Quantum Computers For AI

Guest Post: Why Europe’s Quantum Future Depends on Talent Hubs, Not Just Tech Milestones