A Flexible GKP-State-Embedded Fault-Tolerant Quantum Computation Configuration Based on a Three-Dimensional Cluster State

TL;DR

This paper proposes a flexible, scalable optical fault-tolerant quantum computation architecture using a 3D cluster state embedded with GKP states, leveraging multiple degrees of freedom for enhanced operational flexibility.

Contribution

It introduces a novel 3D cluster state construction in multiple domains and a partially squeezed surface-GKP code for improved fault tolerance in optical quantum computing.

Findings

Fault-tolerant squeezing threshold of 11.5 dB achieved.

Design of optical entanglement generators for diverse entangled pairs.

A scalable, experimentally feasible quantum computation scheme.

Abstract

The integration of diverse quantum resources and the exploitation of more degrees of freedom provide key operational flexibility for universal fault-tolerant quantum computation. In this work, we propose a flexible Gottesman-Kitaev-Preskill-state-embedded fault-tolerant quantum computation architecture based on a three-dimensional cluster state constructed in polarization, frequency, and orbital angular momentum domains. Specifically, we design optical entanglement generators to produce three diverse entangled pairs, and subsequently construct a three-dimensional cluster state via a beam-splitter network with several time delays. Furthermore, we present a partially squeezed surface-GKP code to achieve fault-tolerant quantum computation and ultimately find the optimal choice of implementing the squeezing gate to give the best fault-tolerant performance (the fault-tolerant squeezing threshold is 11.5 dB). Our scheme is flexible, scalable, and experimentally feasible, providing versatile options for future optical fault-tolerant quantum computation architecture.