Projective squeezing for translation symmetric bosonic codes
Abstract
The design of translation symmetric bosonic codes, e.g., Gottesmann-Kitaev-Preskill and squeezed cat codes, is robust against photon loss, but the computation accuracy is limited by the available squeezing level. Here, we introduce the \textit{projective squeezing} (PS) method for computing outcomes for a higher squeezing level by revealing that a linear combination of displacement operators with periodic displacement values constitutes the smeared projector onto the better code space; we also show the analytical relationship between the increased squeezing level and the projection probability. We introduce concrete implementation methods for PS based on linear-combination-of-unitaries and virtual quantum error detection. We also numerically verify our analytical arguments and show that our protocol can mitigate the effect of photon loss.
Cite
@article{arxiv.2403.14218,
title = {Projective squeezing for translation symmetric bosonic codes},
author = {Suguru Endo and Keitaro Anai and Yuichiro Matsuzaki and Yuuki Tokunaga and Yasunari Suzuki},
journal= {arXiv preprint arXiv:2403.14218},
year = {2025}
}