Wavelength conversion for single-photon polarization qubits through continuous variable quantum teleportation

TL;DR

This paper proposes a method for wavelength converting single-photon polarization qubits using continuous variable quantum teleportation, enabling efficient long-distance quantum communication over optical fibers.

Contribution

It introduces a novel wavelength conversion device utilizing continuous variable quantum teleportation with entangled photon sources generated in rubidium vapor cells.

Findings

Efficient conversion between near-infrared and telecom wavelengths for single-photon qubits.

Use of non-degenerate two-mode squeezed states for teleportation.

Potential for enabling long-distance quantum networks.

Abstract

A quantum internet connects remote quantum processors that need interact and exchange quantum signals over a long distance through photonic channels. However, these quantum nodes are usually composed of quantum systems with emitted photons unsuitable for long-distance transmission. Therefore, quantum wavelength conversion to telecom is crucial for long-distance quantum networks based on optical fiber. Here we propose wavelength conversion devices for single-photon polarization qubits using continuous variable quantum teleportation, which can efficiently convert qubits between near-infrared (780/795 nm suitable for interacting with atomic quantum nodes) and telecom wavelength (1300-1500 nm suitable for long-distance transmission). The teleportation uses entangled photon sources (i.e., non-degenerate two-mode squeezed state) that can be generated by four-wave mixing in rubidium atomic vapor cells, with a diamond configuration of atomic transitions. The entangled fields can be emitted in two orthogonal polarizations with locked relative phase, making them especially suitable for interfacing with single-photon polarization qubits. Our work paves the way for the realization of long-distance quantum networks.