A quantum processor based on coherent transport of entangled atom arrays

TL;DR

This paper presents a scalable quantum processor using neutral atom arrays with dynamic, nonlocal connectivity, enabling programmable entanglement and quantum error correction across multiple qubits in two dimensions.

Contribution

The authors demonstrate a quantum architecture that coherently transports entangled atoms in 2D, allowing for complex entangled states and error correction codes, advancing scalable quantum computing.

Findings

Realized programmable generation of entangled graph states.

Implemented surface and toric code states with 19 and 24 qubits.

Measured entanglement entropy, observing non-monotonic dynamics.

Abstract

The ability to engineer parallel, programmable operations between desired qubits within a quantum processor is central for building scalable quantum information systems. In most state-of-the-art approaches, qubits interact locally, constrained by the connectivity associated with their fixed spatial layout. Here, we demonstrate a quantum processor with dynamic, nonlocal connectivity, in which entangled qubits are coherently transported in a highly parallel manner across two spatial dimensions, in between layers of single- and two-qubit operations. Our approach makes use of neutral atom arrays trapped and transported by optical tweezers; hyperfine states are used for robust quantum information storage, and excitation into Rydberg states is used for entanglement generation. We use this architecture to realize programmable generation of entangled graph states such as cluster states and a 7-qubit Steane code state. Furthermore, we shuttle entangled ancilla arrays to realize a surface code with 19 qubits and a toric code state on a torus with 24 qubits. Finally, we use this architecture to realize a hybrid analog-digital evolution and employ it for measuring entanglement entropy in quantum simulations, experimentally observing non-monotonic entanglement dynamics associated with quantum many-body scars. Realizing a long-standing goal, these results pave the way toward scalable quantum processing and enable new applications ranging from simulation to metrology.