Theoretical Framework Proposed for Generating Optical GKP States Using Single-Photon-Added Squeezed Vacuum
A theoretical study has outlined a scheme for generating Gottesman-Kitaev-Preskill (GKP) quantum states using a single-photon-added squeezed vacuum injected into a beam splitter with conditional measurement. GKP states are a key resource for fault-tolerant photonic quantum computing but have historically been difficult to produce experimentally. The proposed method achieves 85% fidelity at 3.76 dB squeezing, outperforming approaches based on squeezed optical odd Schrödinger cat states while relying on more experimentally accessible ingredients.
A preprint submitted to Communications in Theoretical Physics presents a theoretical framework for generating optical GKP states — a critical component for fault-tolerant photonic quantum computing — using a single-photon-added squeezed vacuum (PASV). In the proposed scheme, the PASV, characterized by a squeezing parameter r, is fed into a 50:50 beam splitter, and the GKP state is obtained via conditional measurement at one output port. The study uses fidelity as the metric for how closely the output approximates the ideal finite-energy GKP form, finding a maximum fidelity of 85% at a squeezing level of 3.76 dB. Crucially, the single-photon-added squeezed vacuum is argued to be more experimentally accessible than Schrödinger cat states, which are typically required in competing approaches. The scheme's performance surpasses methods based on squeezed optical odd Schrödinger cat states, positioning it as a more practical pathway toward scalable, fault-tolerant photonic quantum computing. The work remains a preprint and has not yet undergone peer review.
What's missing
The study is a preprint and has not yet been peer-reviewed. Key open questions include whether the 85% fidelity threshold is sufficient for practical fault-tolerant quantum error correction and how the scheme scales with increasing system complexity. The analysis appears to be purely theoretical, with no experimental validation reported.
What different sources said
- arXiv physicsCenter
Theoretical Study for Generating Optical GKP State via a Single-Photon-Added Squeezed Vacuum
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