Photonic qubit encoding interconversion for heterogeneous quantum networking

TL;DR

This paper presents a practical method for converting photon qubit encoding between polarization and time-bin bases, enabling robust quantum communication across heterogeneous networks with fiber transmission.

Contribution

It introduces an interconversion protocol that maintains entanglement fidelity despite polarization fluctuations during fiber transmission.

Findings

Successfully transmits polarization Bell states through fiber with encoding conversion.

Converts sources of infidelity into transmission rate variations.

Enables interfacing different qubit platforms for flexible quantum networks.

Abstract

Quantum information processing, communication, and sensing networks are being developed with various qubit platforms that use different encoding schemes. Connecting quantum network nodes to distribute entanglement requires matching photon qubit basis encoding. In this work, we implement an interconversion protocol which converts photon qubit encoding from the polarization basis to the time-bin basis, transmits the photons through a transport fiber with large fluctuations in polarization, and converts back to polarization encoding for ease of measurement. This interconversion scheme faithfully transmits a polarization Bell state across the transport fiber by converting sources of infidelity to changes in transmission rate. These results illustrate a practical approach for interfacing distinct qubit platforms to enable modular and flexible operation in heterogeneous quantum networks.