Blueprint for a Scalable Photonic Fault-Tolerant Quantum Computer

TL;DR

This paper presents a scalable, fault-tolerant photonic quantum computer architecture that leverages hybrid resource states, integrated photonic chips, and room-temperature operation to advance toward large-scale quantum computing.

Contribution

It introduces a novel architecture combining bosonic qubits and continuous-variable techniques within integrated photonics for scalable, fault-tolerant quantum computation.

Findings

Proposes a hybrid resource state architecture for photonic quantum computing.

Utilizes non-deterministic bosonic qubit generation with continuous-variable gates.

Enables room-temperature operation with scalable fabrication potential.

Abstract

Photonics is the platform of choice to build a modular, easy-to-network quantum computer operating at room temperature. However, no concrete architecture has been presented so far that exploits both the advantages of qubits encoded into states of light and the modern tools for their generation. Here we propose such a design for a scalable and fault-tolerant photonic quantum computer informed by the latest developments in theory and technology. Central to our architecture is the generation and manipulation of three-dimensional hybrid resource states comprising both bosonic qubits and squeezed vacuum states. The proposal enables exploiting state-of-the-art procedures for the non-deterministic generation of bosonic qubits combined with the strengths of continuous-variable quantum computation, namely the implementation of Clifford gates using easy-to-generate squeezed states. Moreover, the architecture is based on two-dimensional integrated photonic chips used to produce a qubit cluster state in one temporal and two spatial dimensions. By reducing the experimental challenges as compared to existing architectures and by enabling room-temperature quantum computation, our design opens the door to scalable fabrication and operation, which may allow photonics to leap-frog other platforms on the path to a quantum computer with millions of qubits.