Joint project: Photonic quantum computers (PhoQuant) - Sub-project: Generation of non-Gaussian quantum states for photonic quantum computing

The aim of this sub-project is to bring together the existing expertise in the field of single photon sources, quantum state tomography and photon detection in order to provide non-Gaussian states, so-called Gottesman-Kitaev-Preskill (GKP) states, as a resource for universal photonic quantum computing through photon catalysis.
The sub-project fits into the overall PhoQuant project, which aims to set up and provide scalable photonic quantum computing. A new proposal from 2019 is being pursued to establish GKP states. As a starting point, single photon states, coherent states (local oscillator) and photon count-resolved detection are used to generate squeezed Schrödinger-Cat states, which can then be merged into GKP states. In principle, GKP states enable universal quantum computing and scalability through quantum error correction. Demonstrating these concepts is the focus of this sub-project.