Transversal Fault Tolerant Distributed Quantum Computing Operations

Abstract

Distributed architectures are a route to scalable quantum computing, but the performance of fault-tolerant operations across noisy inter-module links remains poorly characterized. We present circuit-level simulations of two key distributed primitives: transversal non-local CNOT and logical teleportation using surface and bivariate-bicycle codes. We then simulate the use of these distributed primitives in a major subroutine of common quantum algorithms. The results, enabled by our scalable library Transversal Multiple CodeBlock Simulator, demonstrate that on appropriate devices distributed qLDPC transversal operations can outperform surface code lattice surgery and enable efficient parallel computation with lower Bell pair consumption. Notably, we find that the non-local CNOT achieves up to an order of magnitude lower logical error rates than teleportation at the same code distance and noise levels. We further show that code distances of $d \approx 11$ at physical error rate $p \sim 10^{-4}$ and $d \approx 29$ at $p \sim 10^{-3}$, with $p_{\mathrm{ebit}}=10p$, are sufficient to achieve logical error rates below $10^{-12}$, enabling large-scale algorithms. These results provide critical guidance for architecture and code selection in distributed quantum computing.