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arXiv · 2609.34774

Cubic Phase Gate with a Trapped Ion Oscillator

Nigel Benjamin Lee Junsheng·Eugene Koh Jun Wei·Mu Young Kim·Dzmitry Matsukevich
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Abstract

The motional modes of trapped ions are promising candidates for continuous-variable (CV) quantum computation and simulation. However, to achieve a universal gate set for CV quantum computation, anharmonic nonlinear unitaries are required. Here, we experimentally demonstrate a protocol that allows us to approximate the cubic phase gate. By numerically optimizing the phase angles and amplitudes of a set of state-dependent force pulses, we demonstrate the cubic phase gate for both vacuum and low-$α$ coherent state inputs and verify its performance. Our protocol can also be extended to approximate other nonlinear unitaries.

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Nigel Benjamin Lee Junsheng, Eugene Koh Jun Wei, Mu Young Kim, Dzmitry Matsukevich. 2026-09-28. Cubic Phase Gate with a Trapped Ion Oscillator. https://arxiv.org/abs/2609.34774

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