Spin-Photon Entanglement of a Single Er^{3+} Ion in the Telecom Band

Entanglement between photons and a quantum memory is a key component of quantum repeaters, which allow long-distance quantum entanglement distribution in the presence of fiber losses. Spin-photon entanglement has been implemented with a number of different atomic and solid-state qubits with long spi...

Full description

Saved in:
Bibliographic Details
Main Authors: Mehmet T. Uysal, Łukasz Dusanowski, Haitong Xu, Sebastian P. Horvath, Salim Ourari, Robert J. Cava, Nathalie P. de Leon, Jeff D. Thompson
Format: Article
Language:English
Published: American Physical Society 2025-03-01
Series:Physical Review X
Online Access:http://doi.org/10.1103/PhysRevX.15.011071
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Entanglement between photons and a quantum memory is a key component of quantum repeaters, which allow long-distance quantum entanglement distribution in the presence of fiber losses. Spin-photon entanglement has been implemented with a number of different atomic and solid-state qubits with long spin coherence times, but none directly emit photons into the 1.5-μm telecom band where losses in optical fibers are minimized. Here, we demonstrate spin-photon entanglement using a single rare earth ion in the solid-state Er^{3+} coupled to a silicon nanophotonic cavity, which directly emits photons at 1532.6 nm. We infer an entanglement fidelity of 73(3)% after propagating through 15.6 km of optical fiber. This work opens the door to large-scale quantum networks based Er^{3+} ions, leveraging scalable silicon device fabrication and spectral multiplexing.
ISSN:2160-3308