Crosstalk-Resilient Quantum MIMO for Scalable Quantum Communications

TL;DR

This paper introduces a coding strategy using GKP codes to mitigate crosstalk in quantum multiplexing, enabling scalable quantum communication by preserving logical information despite mode interference.

Contribution

It proposes a novel encoding method with rigorous conditions for perfect transmission and a gauge-fixing decoder, advancing crosstalk resilience in quantum networks.

Findings

Effective crosstalk mitigation demonstrated via numerical simulations

Conditions for perfect transmission established

Tradeoff between rate and fidelity analyzed

Abstract

We address the challenge of crosstalk in quantum multiplexing -an obstacle to scaling throughput in quantum communication networks. Crosstalk arises when physically coupled quantum modes interfere, degrading signal fidelity. We propose a mitigation strategy based on encoding discrete-variable (DV) quantum information into continuous-variable (CV) bosonic modes using Gottesman-Kitaev-Preskill (GKP) codes. By analyzing the effect of mode-mixing interference, we show that under specific noise strength conditions, the interaction can be absorbed into a gauge subsystem that leaves the logical content intact. We provide rigorous conditions for perfect transmission in the ideal case, derive the structure of the output codes and prove the existence of a gauge-fixing decoder enabling recovery of the logical information. Numerical simulations under displacement Gaussian noise illustrate the fidelity behavior and rate-fidelity tradeoff. Our results establish a coding-theoretic foundation for crosstalk-resilient multiplexing in quantum networks.