Hyperbolic Cluster States for Fault-Tolerant Measurement-Based Quantum Computing

TL;DR

This paper introduces hyperbolic cluster states for fault-tolerant measurement-based quantum computing, demonstrating their advantages in scalability and error correction through numerical simulations.

Contribution

It generalizes 3D cluster states to hyperbolic geometries, showing they maintain fault-tolerance thresholds and support constant encoding rates, reducing qubit overhead.

Findings

Hyperbolic cluster states have fault-tolerance thresholds comparable to Euclidean ones.

They support a constant encoding rate in the thermodynamic limit.

Numerical simulations confirm their robustness under realistic noise models.

Abstract

Fault-tolerant measurement-based quantum computing (MBQC) provides a compelling framework for fault-tolerant quantum computation, in which quantum information is processed through single-qubit measurements on a three-dimensional entangled resource known as cluster state. To date, this resource has been predominantly studied on Euclidean lattices, most notably in the Raussendorf-Harrington-Goyal (RHG) construction, which underlies topological fault tolerance in MBQC. In this work, we introduce the hyperbolic cluster state, a generalization of the three-dimensional cluster state to negatively curved geometries, obtained via the foliation of periodic hyperbolic lattices. We present an explicit construction of hyperbolic cluster states and investigate their fault-tolerant properties under a realistic circuit-level depolarizing noise model. Using large-scale numerical simulations, we perform memory experiments to characterize their logical error rates and decoding performance. Our results demonstrate that hyperbolic cluster states exhibit a fault-tolerance threshold comparable to that of the Euclidean RHG cluster state, while simultaneously supporting a constant encoding rate in the thermodynamic limit. This represents a substantial improvement in qubit overhead relative to conventional cluster-state constructions. These findings establish hyperbolic geometry as a powerful and experimentally relevant resource for scalable, fault-tolerant MBQC and open new avenues for leveraging negative curvature in quantum information processing.