Continuous-variable quantum-computing (CVQC) is the most scalable implementation of QC to date but requires non-Gaussian resources to allow exponential speedup and quantum correction, using error encoding such as Gottesman-Kitaev-Preskill (GKP) states. However, GKP state generation is still an experimental challenge. We show theoretically that photon catalysis, the interference of coherent states with single-photon states followed by photon-number-resolved detection, is a powerful enabler for non-Gaussian quantum state engineering such as exactly displaced single-photon states and M-symmetric superpositions of squeezed vacuum (SSV), including squeezed cat states (M=2). By including photon-counting based state breeding, we demonstrate the potential to enlarge SSV states and produce GKP states.
@article{arxiv.1903.01925,
title = {Non-Gaussian and Gottesman-Kitaev-Preskill state preparation by photon catalysis},
author = {Miller Eaton and Rajveer Nehra and Olivier Pfister},
journal= {arXiv preprint arXiv:1903.01925},
year = {2020}
}