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.
@article{arxiv.2507.22253,
title = {Measurement-induced cubic phase state generation},
author = {Harsh Kashyap and Denis A. Kopylov and Polina R. Sharapova},
journal= {arXiv preprint arXiv:2507.22253},
year = {2026}
}