Epsilon-Near-Zero Grids for On-chip Quantum Networks

TL;DR

This paper introduces a novel on-chip quantum network design using epsilon-near-zero materials, significantly enhancing quantum information coherence and scalability at room temperature.

Contribution

It proposes and numerically demonstrates a robust ENZ-based quantum network that protects against decoherence, enabling larger and more reliable on-chip quantum photonic circuits.

Findings

Quantum information coherence length of 434 nm in ENZ network

Operation at room temperature

Coherence length exceeds state-of-the-art plasmonic systems by over 40 times

Abstract

Realization of an on-chip quantum network is a major goal in the field of integrated quantum photonics. A typical network scalable on-chip demands optical integration of single photon sources, optical circuitry and detectors for routing and processing of quantum information. Current solutions either notoriously experience considerable decoherence or suffer from extended footprint dimensions limiting their on-chip scaling. Here we propose and numerically demonstrate a robust on-chip quantum network based on an epsilon-near-zero (ENZ) material, whose dielectric function has the real part close to zero. We show that ENZ materials strongly protect quantum information against decoherence and losses during its propagation in the dense network. As an example, we model a feasible implementation of an ENZ network and demonstrate that quantum information can be reliably sent across a titanium nitride grid with a coherence length of 434 nm, operating at room temperature, which is more than 40 times larger than state-of-the-art plasmonic analogs. Our results facilitate practical realization of large multi-node quantum photonic networks and circuits on-a-chip.