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arXiv · 2507.22253

Measurement-induced cubic phase state generation

Harsh Kashyap·Denis A. Kopylov·Polina R. Sharapova
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Abstract

The cubic phase state constitutes a nonlinear resource that is essential for universal quantum computing protocols. However, constructing such non-classical states faces many challenges. In this work, we present a protocol for generating a cubic phase state with high fidelity. The protocol is based on a set of Gaussian operations assisted by a detection operation. To find the proper set of parameters that results in both high fidelity and high detection probability, we provide a numerical multiparameter optimization. We investigate a broad range of target states and study how parameter imperfections influence fidelity.

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Harsh Kashyap, Denis A. Kopylov, Polina R. Sharapova. 2025-07-29. Measurement-induced cubic phase state generation. https://arxiv.org/abs/2507.22253

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