Experimental Quantum Optics
and Photonics Group


Latest News

Demonstration of weighted graph optimization on a Rydberg atom array using local light-shifts
Neutral atom arrays have emerged as a versatile platform towards scalable quantum computation and optimisation. In this paper we present first demonstrations of weighted graph optimization on a Rydberg atom array using annealing with local light-shifts. We verify the ability to prepare weighted graphs in 1D and 2D arrays, including embedding a five vertex non-unit disk graph using nine physical qubits. We find common annealing ramps leading to preparation of the target ground state robustly over a substantial range of different graph weightings. This work provides a route to exploring large-scale optimisation of non-planar weighted graphs relevant for solving relevant real-world problems. For more details see PRX Quantum 6, 010301 (2025) or arXiv:2404.02658.
Benchmarking the algorithmic performance of near-term neutral atom processors
We have performed theoretical work on algorithmic benchmarking to evaluate the performance of near-term neutral atom processors accounting for realistic gate errors and atom loss. We show that for a 9 qubit system a quantum volume of 29 is attainable, the maximum possible for this size of processor, highlighting the viability of using near-term neutral atom hardware for small-scale algorithms. For more details see arXiv:2402.02127.
Commensurate and incommensurate 1D interacting quantum systems
We use dynamically varying microscopic light potentials in a quantum-gas microscope to study commensurate and incommensurate 1D systems of interacting bosonic atoms in an optical lattice Nat Communications 15, 474 (2024).
Interspecies Förster resonances of Rb-Cs Rydberg d-states for enhanced multi-qubit gate fidelities
We present an analysis of interspecies interactions between Rydberg d-states of rubidium and cesium. We identify the Förster resonance channels offering the strongest interspecies couplings, demonstrating the viability for performing high-fidelity two- and multi-qubit CkZ gates up to k=4, including accounting for blockade errors evaluated via numerical diagonalization of the pair-potentials. Our results show d-state orbitals offer enhanced suppression of intraspecies couplings compared to s-states, making them well suited for use in large-scale neutral atom quantum processors. For more details see arXiv:2401.02308.

Recent publications

Speeding Up Quantum Measurement Using Space-Time Trade-Off
Physical Review Letters 134, 080801 (2025)
We present a scheme for speeding up quantum measurement. The scheme builds on previous protocols that entangle the system to be …
A Review and Collection of Metrics and Benchmarks for Quantum Computers: definitions, methodologies and software
arXiv (2025)
Quantum computers have the potential to provide an advantage over classical computers in a number of areas. Numerous metrics to …
Demonstration of Weighted-Graph Optimization on a Rydberg-Atom Array Using Local Light Shifts
PRX Quantum 6, 010301 (2025)
Neutral-atom arrays have emerged as a versatile platform toward scalable quantum computation and optimization. In this paper, we …
Interspecies Förster resonances for Rb-Cs Rydberg d-states for enhanced multi-qubit gate fidelities
Physical Review Research 6, 013293 (2024)
Benchmarking the algorithmic performance of near-term neutral atom processors
(2024)
Neutral atom quantum processors provide a viable route to scalable quantum computing, with recent demonstrations of high-fidelity and …