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arXiv · 2504.03853

Multiqubit GHZ state preparation with $^{171}\text{Yb}^+$ ions for frequency standards

A. E. Korolkov·I. V. Zalivako·A. S. Borisenko·V. N. Smirnov·P. A. Kamenskikh·I. A. Semerikov·K. Yu. Khabarova·N. N. Kolachevsky
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Abstract

Multiqubit Greenberger-Horne-Zeilinger (GHZ) state preparation is demonstrated on two to eight qubits in the chain of ten $^{171}Yb^+$ ions in the linear Paul trap with a sequence of single-qubit and two-qubit operations and pulsed dynamical decupling. Fidelity of the 8-qubit GHZ state is estimated to be $58.9 \pm 0.6\%$. The expected enhanced sensitivity of the parity oscillations phase to the analyzing pulse phase is observed. This result is a step towards a multi-ion optical clock with ytterbium ions with frequency averaging following $1/N$ scaling law in contrast to the slower $1/\sqrt{N}$ scaling for an ensemble of independent particles in case when the decoherence is dominated by the spontaneous decay.

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A. E. Korolkov, I. V. Zalivako, A. S. Borisenko, V. N. Smirnov, P. A. Kamenskikh, I. A. Semerikov, K. Yu. Khabarova, N. N. Kolachevsky. 2025-04-04. Multiqubit GHZ state preparation with $^{171}\text{Yb}^+$ ions for frequency standards. https://arxiv.org/abs/2504.03853

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