High-fidelity entanglement and coherent multi-qubit mapping in an atom array

TL;DR

This paper demonstrates high-fidelity entanglement creation and coherent state mapping across multiple qubits in Ytterbium-171 atom arrays, enabling advanced quantum information processing and bridging different quantum applications.

Contribution

It introduces a method for generating and coherently mapping entangled states across multiple qubits in Ytterbium-171 tweezer arrays, including novel disorder-robust pulses and high-fidelity error detection.

Findings

Coherent transfer of 20-atom GHZ states between Rydberg and nuclear spin qubits.

Achieved >90% Rydberg decay detection with clock-qubit-based spin detection.

Error-detected two-qubit gate fidelity of 99.78%.

Abstract

Neutral atoms in optical tweezer arrays possess broad applicability for quantum information science, in computing, simulation, and metrology. Among atomic species, Ytterbium-171 is unique as it hosts multiple qubits, each of which is impactful for these distinct applications. Consequently, this atom is an ideal candidate to bridge multiple disciplines, which, more broadly, has been an increasingly effective strategy within the field of quantum science. Realizing the full potential of this synergy requires high-fidelity generation and transfer of many-particle entanglement between these distinct qubit degrees of freedom, and thus between these distinct applications. Here we demonstrate the creation and coherent mapping of entangled quantum states across multiple qubits in Ytterbium-171 tweezer arrays. We map entangled states onto the optical clock qubit from the nuclear spin qubit or the Rydberg qubit. We coherently transfer up to 20 atoms of a $Z_2$-ordered Greenberger-Horne-Zeilinger (GHZ) state from the interacting Rydberg manifold to the metastable nuclear spin manifold. The many-body state is generated via a novel disorder-robust pulse in a two-dimensional ladder geometry. We further find that clock-qubit-based spin detection applied to Rydberg and nuclear spin qubits facilitates atom-loss-detectable qubit measurements and $>90\%$ Rydberg decay detection. This enables mid-circuit and delayed erasure detection, yielding an error-detected two-qubit gate fidelity of $99.78(4)\%$ in the metastable qubits. This error detection also enables Rydberg qubit evolution with an effective lifetime of $1.2(2)$ ms, enhancing the fidelity of the observed many-body dynamics. These results establish a versatile architecture that advances multiple fields of quantum information science while also establishing bridges between them.