Frequency-bin entanglement-based Quantum Key Distribution: Experimental setup and device spectra.

Frequency-bin entanglement-based Quantum Key Distribution

The researchers demonstrated the first complete implementation of entanglement-based quantum key distribution using frequency-bin encoding on a silicon photonic chip, overcoming phase noise challenges to achieve stable transmission over 26 kilometers of fiber with a secure key rate of at least 4.5 bits per second.

Quantum sensing with duplex qubits of silicon vacancy centers in SiC at room temperature

Quantum sensing with duplex qubits of silicon vacancy centers in SiC at room temperature

Silicon vacancy centers in Silicon Carbide show promise as room-temperature qubits for quantum sensing applications, with researchers demonstrating that simultaneously operating both transitions in the spin-3/2 quartet through a novel duplex qubit scheme doubles the signal contrast and improves sensitivity compared to conventional single-qubit approaches.

Industrial 300 mm wafer processed spin qubits in natural silicon/silicon-germanium: Device architecture and charge control.

Industrial 300 mm wafer processed spin qubits in natural silicon/silicon-germanium

A landmark study demonstrates fully industrialized fabrication of high-performance silicon quantum dots using 300mm semiconductor wafer processes, achieving impressive metrics including sub-2μeV charge noise, 1-second spin relaxation times, and 99% gate fidelities, while incorporating monolithic cobalt micromagnets, thus establishing a viable pathway for scaling quantum computing through existing semiconductor manufacturing infrastructure.

Scaling of the one-norm and number of unique, non-zero coefficients (NNZ) for test systems.

First-Quantization: A Quantum Leap for Molecular Energy Solvers

Researchers have developed a novel first-quantization method for quantum computing that achieves significant improvements in efficiency for molecular energy calculations across arbitrary basis sets, demonstrating both asymptotic speedup in molecular orbital calculations and orders-of-magnitude resource reductions when using dual plane waves compared to second-quantization approaches.

An artist’s impression of an analog quantum computer in which atoms are manipulated by lasers to simulate quantum many-body systems. Credit: Image courtesy of Nikita Zemlevskiy, Henry Froland, and Stephan Caspar

Quantum Uncertainty Framework Boosts Simulation Reliability

A newly developed framework enhances the predictive power of analog quantum simulations by systematically quantifying and minimizing uncertainties in theoretical approximations used to represent complex quantum many-body systems in Rydberg-atom quantum computers.

ORNL scientists successfully combined key quantum photonic capabilities on a single chip for the first time. Credit: ORNL, U.S. Dept. of Energy

Silicon Chip Breakthrough: Quantum Photonics for Fiber Networks

Silicon photonic integrated circuit developed by ORNL scientists combines a bidirectionally pumped microring resonator with polarization splitter-rotators to generate broadband, high-fidelity polarization-entangled photons across 116 frequency-bin pairs compatible with existing fiber-optic networks, marking a significant advancement toward a scalable quantum internet.

Enhancing Majorana stability with a three-site Kitaev chain

Scalable Kitaev Chains for Quantum Computing

A QuTech-led research team successfully created a three-site Kitaev chain in a hybrid InSb/Al nanowire that demonstrates enhanced stability of Majorana zero modes compared to two-site chains, marking significant progress toward scalable topological quantum computing.

Quantum skyrmions through noise.

Topological Quantum Resilience: Skyrmions Defeat Noise Barrier

Researchers have demonstrated that quantum information encoded in topological skyrmions remains resilient to environmental noise even as entanglement deteriorates, representing a breakthrough “digitization” approach that could revolutionize practical quantum technologies without requiring complex compensation strategies.

cientists have unlocked the full statistical fingerprint of quantum entanglement, enabling device testing without needing to know how those devices work. Credit: J-D Bancal (IPhT)

Decoding Quantum Entanglement: The Language of Hidden Statistics

This research fully maps the statistical outcomes of quantum entanglement, enabling complete description of partially entangled states through mathematical transformation, establishing theoretical limits of quantum physics while opening new avenues for secure quantum testing, communications, and computing without requiring assumptions about device properties.

Setup of free-space CV-QKD

Robust Continuous-Variable Quantum Key Distribution in Daylight Conditions

The research demonstrates a breakthrough Gaussian modulated coherent state continuous-variable quantum key distribution system that operates effectively in daylight and rainy conditions over an 860-meter free-space link, achieving high secure key rates without complex filtering by using a 1550 nm wavelength and polarization-multiplexed local oscillator, significantly advancing practical quantum communication applications.

Experimental setup of the OPA at 1553 nm. DFB, distributed feedback; PPLN, periodically poled lithium niobate.

New 193nm Laser Creates Vortex Beams for Advanced Chipmaking

A groundbreaking compact solid-state laser system generates 193-nm coherent light for semiconductor lithography while also producing the first-ever 193-nm vortex beam carrying orbital angular momentum, offering superior coherence and potential applications in wafer processing, defect inspection, and quantum technologies.

Overview of OQTOPUS. Credit: OQTOPUS Team

OQTOPUS: Japan’s Open Quantum OS for Cloud

OQTOPUS is a groundbreaking open-source quantum computing operating system created collaboratively by Japanese institutions, offering comprehensive customization from setup to execution while significantly reducing implementation complexity, thus making quantum computing more accessible to a broader range of users and accelerating its practical adoption.

Simulating two-dimensional lattice QED with matter fields.

Qudit Quantum Computing Breaks New Ground in Gauge Theory

Researchers from the University of Innsbruck and the University of Waterloo have achieved a breakthrough in quantum computing by using qudits (quantum units with multiple values) instead of traditional qubits to efficiently simulate quantum electrodynamics in two dimensions, demonstrating magnetic field interactions between particles and opening new possibilities for solving previously intractable problems in particle physics.

High-precision quantum gates with diamond spin qubits

High-precision quantum gates with diamond spin qubits

QuTech researchers, collaborating with Fujitsu and Element Six, have achieved a significant quantum computing milestone by demonstrating diamond spin-based quantum gates with error rates below 0.1%—satisfying a critical threshold for quantum error correction and bringing us one step closer to scalable quantum computation.

Minimum cost flow.

Networking quantum networks with minimum cost aggregation

A quantum internet protocol using minimum cost aggregation and network concatenation enables efficient distribution of entangled bits with bounded error between arbitrary clients across multiple quantum networks regardless of distance, overcoming previous limitations and forming the necessary foundation for global-scale quantum networking.

Quantum photonic chip for the realization of eight-dimensional quantum superdense coding.

Realizing ultrahigh capacity quantum superdense coding on quantum photonic chip

A research team has achieved a breakthrough in quantum communication by implementing an eight-dimensional quantum superdense coding protocol on a 16-mode photonic chip, demonstrating an unprecedented channel capacity exceeding 3 bits through the generation of high-fidelity entangled quDit states and efficient Bell state measurements that distinguish eleven orthogonal states, significantly outperforming classical communication limits.

Conceptual schematic and performance advantage of the in-cavity protocol.

Quantum-Enhanced Dark Matter Detection Beyond Rayleigh Limits

Researchers propose a novel quantum sensing protocol that uses in-cavity squeezed states and optimized transient control to mitigate the Rayleigh curse limitation, enabling more sensitive dark matter detection in microwave cavities without requiring non-Gaussian quantum resources that would be incompatible with the strong magnetic fields needed for axion searches.

Experimental setup demonstrating entanglement between two photons. (a) The experimental setup: A 405 nm laser illuminates a β-barium borate (BBO) crystal to generate entangled photon pairs, with the idler photon in the upper arm and the signal photon in the lower arm. The metasurface (MS) encodes polarization information into holographic letters. (b) The signal photon’s hologram observed without a polarizer (eraser) in the idler arm. (c-f) Holograms with different polarizer orientations in the idler arm. The polarizer set to horizontal (H), diagonal (D), vertical (V), and antidiagonal (A) orientations selectively erases the corresponding letter in the holographic output. Credit: H. Liang et al., doi 10.1117/1.AP.7.2.026006

Quantum Holograms: Metasurfaces Unlock New Frontiers in Quantum Entanglement

Researchers have successfully created quantum holograms using metasurfaces, enabling unprecedented control over entangled photon pairs where the polarization of one photon can selectively erase holographic content in its partner, demonstrating precise quantum control with applications in secure communication and anti-counterfeiting technology.

An illustration of our stochastic QSP construction.

Halving the cost of quantum algorithms with randomization

Stochastic Quantum Signal Processing integrates randomized compiling into quantum signal processing to achieve quadratic error suppression (ϵ → O(ϵ²)), reducing query complexity by nearly half across multiple quantum algorithms including Hamiltonian simulation, phase estimation, ground state preparation, and matrix inversion.

Nonlinear superconducting resonator circuit for investigating dissipative phase transitions. Credit: Guillaume Beaulieu (EPFL)

Quantum Leap: New Phase Transitions Stabilize Computing

Researchers successfully observed “dissipative phase transitions” in quantum systems using a superconducting Kerr resonator at near-absolute zero temperatures, revealing phenomena like “squeezing,” metastability, and “critical slowing down” that could revolutionize quantum computing and sensing technologies through enhanced stability and precision.

QIA researchers create first Operating System for Quantum Networks

QNodeOS: Revolutionizing Quantum Networks

Researchers from the Quantum Internet Alliance have created QNodeOS, the first operating system for quantum networks, which abstracts hardware complexity to enable easier development of quantum networking applications across different hardware platforms, marking a crucial step toward making quantum internet technology accessible and practical.

Beyond Classical: D-Wave First to Demonstrate Quantum Supremacy on Useful, Real-World Problem

D-Wave First to Demonstrate Quantum Supremacy

D-Wave Quantum Inc. has achieved the world’s first demonstration of quantum computational supremacy on a useful real-world problem, using their Advantage2 prototype quantum annealer to perform complex magnetic materials simulations in minutes that would take a classical supercomputer nearly one million years and consume more than the world’s annual electricity.

The Hubbard model in various sizes.

Quantum Zeno Monte Carlo for computing observables

The Quantum Zeno Monte Carlo algorithm bridges the gap between noisy intermediate-scale quantum and fault-tolerant quantum computing eras by offering polynomial computational complexity and resilience to both device noise and Trotter errors without requiring initial state overlap or variational parameters, as demonstrated on IBM’s NISQ devices with up to 12 qubits.