Universal quantum operations and ancilla-based read-out for tweezer clocks.

Enhancing the precision of measurements by harnessing entanglement is a long-sought goal in quantum metrology. Yet attaining the best sensitivity allowed by quantum theory in the presence of noise is an outstanding challenge, requiring optimal probe-state generation and read-out strategies. Neutral-atom optical clocks, which are the leading systems for measuring time, have shown recent progress in terms of entanglement generation but at present lack the control capabilities for realizing such schemes.

Benchmarking highly entangled states on a 60-atom analogue quantum simulator.

Quantum systems have entered a competitive regime in which classical computers must make approximations to represent highly entangled quantum states. However, in this beyond-classically-exact regime, fidelity comparisons between quantum and classical systems have so far been limited to digital quantum devices, and it remains unsolved how to estimate the actual entanglement content of experiments. Here, we perform fidelity benchmarking and mixed-state entanglement estimation with a 60-atom analogue Rydberg quantum simulator, reaching a high-entanglement entropy regime in which exact classical simulation becomes impractical.

Erasure conversion in a high-fidelity Rydberg quantum simulator.

Minimizing and understanding errors is critical for quantum science, both in noisy intermediate scale quantum (NISQ) devices and for the quest towards fault-tolerant quantum computation. Rydberg arrays have emerged as a prominent platform in this context with impressive system sizes and proposals suggesting how error-correction thresholds could be significantly improved by detecting leakage errors with single-atom resolution, a form of erasure error conversion. However, two-qubit entanglement fidelities in Rydberg atom arrays have lagged behind competitors and this type of erasure conversion is yet to be realized for matter-based qubits in general.

Shotgun Metagenomics Reveals Impacts of Copper and Water Heater Anodes on Pathogens and Microbiomes in Hot Water Plumbing Systems.

Hot water building plumbing systems are vulnerable to the proliferation of opportunistic pathogens (OPs), including and . Implementation of copper as a disinfectant could help reduce OPs, but a mechanistic understanding of the effects on the microbial community under real-world plumbing conditions is lacking. Here, we carried out a controlled pilot-scale study of hot water systems and applied shotgun metagenomic sequencing to examine the effects of copper dose (0-2 mg/L), orthophosphate corrosion control agent, and water heater anode materials (aluminum vs magnesium vs powered anode) on the bulk water and biofilm microbiome composition.