arXiv subjects

Lukas Sturm

Publications and source records attributed to Lukas Sturm.

3 recordsLinked to original sources

arXiv2026

Efficient Assembly of a Defect-Free Quantum Register of 1024 Neutral-Atom Qubits

Low-entropy arrays of atomic quantum systems in optical tweezers offer unique prospects for fundamental research on few- and many-body systems as well as for extended applications in quantum technology. The significance of this approach relies on the achievable system size, its uniformity, and the rate of qubit allocation. We propel the neutral-atom quantum-technology platform by the rapid assembly of a regular two-dimensional quantum register of up to 1024 atomic qubits, enabled by a novel implementation of intensity-homogenized tweezer arrays and parallelized atom transport. Our highly efficient microoptical architecture modularizes intensity equalization and tweezer patterning in separate functional units, eliminating restrictions that arise for high-power, high-resolution, and large-scale light-field control within a single device. Arrays of precise grid structure, trap depth, and vibrational frequency with more than 3500 sites are demonstrated. Individual sites are interconnected by up to 50 parallelized transport tweezers with intensity and position control in real-time for swift qubit relocation. Multi-tweezer transport enables the operation of target patterns of up to 32 x 32 sites with sustained near-unity filling fraction. These results boost neutral-atom quantum information science above the kiloqubit level.

quant-ph↗

arXiv2025

Model-Based Real-Time Synthesis of Acousto-Optically Generated Laser-Beam Patterns and Tweezer Arrays

Acousto-optic deflectors (AOD) enable spatiotemporal control of laser beams through diffraction at an ultrasonic grating that is controllable by radio-frequency (rf) waveforms. These devices are a widely used tool for high-bandwidth random-access scanning applications, such as optical tweezers in quantum technology. A single AOD can generate multiple optical tweezers by multitone rf input in one dimension. Two-dimensional (2D) patterns can be realized with two perpendicularly oriented AODs. As the acousto-optical response depends nonlinearly on the applied frequency components, phases, and amplitudes, and in addition experiences dimensional coupling in 2D setups, intensity regulation becomes a unique challenge. Guided by coupled-wave theory and experimental observations, we derive a compute-efficient model which we implement on a graphics processing unit. Only one-time sampling of single-tone laser-power calibration is needed for model parameter determination, allowing for straight-forward integration into optical instruments. We implement and experimentally validate an open-loop diffraction efficiency control system that enables programmable 2D multibeam trajectories with intensity control applied at every time step during digital signal generation, overcoming the limited flexibility, pattern-size constraints, and bandwidth limitations of methods using precalculation and precalibration of a predefined pattern set or closed-loop feedback. The system is capable of stable real-time waveform streaming of arrays with up to 50 x 50 tweezers with minimal time resolution of 1.4 ns (700 MS/s) and a peak latency below 257 microseconds for execution of newly requested patterns. Reactive, real-time 2D multibeam laser patterning and scanning with strict intensity matching will substantially benefit parallelization and increasing data rates in materials processing, microscopy, and optical tweezers.

physics.optics↗

arXiv2024

Supercharged two-dimensional tweezer array with more than 1000 atomic qubits

We report on the realization of a large-scale quantum-processing architecture surpassing the tier of 1000 atomic qubits. By tiling multiple microlens-generated tweezer arrays, each operated by an independent laser source, we can eliminate laser-power limitations in the number of allocatable qubits. Already with two separate arrays, we implement combined 2D configurations of 3000 qubit sites with a mean number of 1167(46) single-atom quantum systems. The transfer of atoms between the two arrays is achieved with high efficiency. Thus, supercharging one array designated as quantum processing unit with atoms from the secondary array significantly increases the number of qubits and the initial filling fraction. This drastically enlarges attainable qubit cluster sizes and success probabilities allowing us to demonstrate the defect-free assembly of clusters of up to 441 qubits with persistent stabilization at near-unity filling fraction over tens of detection cycles. The presented method substantiates neutral atom quantum information science by facilitating configurable geometries of highly scalable quantum registers with immediate application in Rydberg-state mediated quantum simulation, fault-tolerant universal quantum computation, quantum sensing, and quantum metrology.

quant-ph↗