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DOE OSTI · 1874041

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

Luo, Xi-Wang·Zhang, Chuanwei·Novikova, Irina·Qian, Chen·Du, Shengwang
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Abstract

A quantum internet connects remote quantum processors that need to interact and exchange quantum signals over a long distance through photonic channels. However, these quantum nodes operate at the wavelength ranges unsuitable for long-distance transmission. Therefore, quantum wavelength conversion to telecom bands 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 that 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 fields (i.e., nondegenerate two-mode squeezed state) that can be generated by four-wave mixing in a rubidium atomic gas using 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. Furthermore, our work may pave the way for the realization of long-distance quantum networks.

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74 ATOMIC AND MOLECULAR PHYSICSPhotonQuantum information processing with continuous variablesQuantum networksQuantum opticsQuantum teleportationQubitpolarizationquantum networksquantum opticsquantum teleportationqubit

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Luo, Xi-Wang, Zhang, Chuanwei, Novikova, Irina, Qian, Chen, Du, Shengwang. 2022-05-31. Wavelength conversion for single-photon polarization qubits through continuous-variable quantum teleportation. https://doi.org/10.1103/physreva.105.052444

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