September 5, 2026

Twin-photon generation in a silicon nitride microresonatorTier 3

Photonic chips with silicon nitride (Si_3N_4) microring resonators are well established as heralded single-photon sources, but their operation as frequency-degenerate twin-photon sources has not previously been demonstrated. Here, we realise a twin-photon source at telecommunication wavelengths in a Si_3N_4 ring microresonator via an inverse four-wave m...

Non-local Magic: closed-form solution and equivalence with magic of purificationTier 3

Non-local magic quantifies the non-stabilizerness of a bipartite quantum state that cannot be removed by local unitary transformations. Despite its natural definition, its evaluation generally requires a difficult optimization over local unitaries. Here, we show that for the log-stabilizer fidelity this optimization admits an exact closed-form analytic solution depending onl...

Gravitationally Induced Entanglement Across an Event HorizonTier 3

It has long been assumed that a particle---having crossed a black hole event horizon unentangled with another particle in the exterior universe---can no longer dynamically entangle with that particle. Here, we demonstrate within a gravitational retarded-potential model that entanglement can in fact be created from scratch between freely falling spatial superpositions across...

Strongly anisotropic non-Kramers electron spin as a quantum coherence probe of angular fluctuationsTier 3

Strongly anisotropic non-Kramers rare-earth ions combine giant longitudinal g-factors with a vanishing transverse component imposed by time-reversal symmetry, a combination that makes their spin transitions exquisitely sensitive to the orientation of the applied magnetic field. We show that this sensitivity carries a dual identity: it is simultaneously an overlooked decohere...

Approximate maximum-likelihood decoding via truncated free energiesTier 3

Maximum-likelihood decoding (MLD) achieves the minimum logical error rate of stabilizer codes under known i.i.d. Pauli noise, but its exact evaluation is \#P-hard. Practical pipelines therefore approximate MLD by minimum-weight decoding (MWD), retaining only the lowest-weight recovery per syndrome and discarding the coset degeneracy. The minimum-weight search is in turn impl...

Analog quantum simulation of bosonic and anyonic models with flux-driven transmonsTier 3

When quantum particles interact, many-body phenomena that are hard to simulate classically emerge. Quantum analog simulation offers an alternative in which the target system's dynamics is directly realized in controllable quantum hardware. Here, we give a general protocol for simulating the Bose-Hubbard and anyon-Hubbard models using lattices of capacitively coupled flux-tun...

On the geometry and typicality of quantum magicTier 3

We prove that, for an n-qubit system of dimension d=2^n, every state satisfying Tr(ρ^2)≤1/(d-a_(ast)), with a_(ast)=0.458327⋯, lies inside the stabilizer polytope and is therefore magic-free. Combining this result with general geometric properties of high-dimensional polytopes, we establish quantitative estimates for the Hilbert--Schmidt inradius...

Quantum thermalization achieves optimal approximate quantum error correctionTier 3

Quantum thermalization explains how an isolated many-body system naturally evolves towards a thermal state, rendering information about the initial conditions inaccessible to local measurements. This is precisely the mechanism utilized in quantum error correction, where information is protected by design through a nonlocal encoding. In this work, we leverage this connection...

Brian Gaucher (ERVA): Why engineering, not physics, now limits quantum progressTier 2

QuFi Launches Post-Quantum Verification Platform for Digital AssetsTier 2

Scientek and Classiq Partner to Accelerate Quantum Software Adoption in TaiwanTier 2

Europe Looks to Quantum Act to Turn Research Strength Into IndustryTier 2

Quantum Computing Challenges Holding Back Practical Quantum ComputersTier 2

RIKEN Adopts QunaSys QURI SDK for Quantum-HPC Hybrid ComputingTier 2