Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Quantum Computing, Communication, and Simulation

Towards optical quantum networks based on rare-earth ions and nanophotonics

Andrei Faraon, Andrei Ruskuc, Ioana Craiciu, Jonathan M. Kindem, John G. Bartholomew, Jake Rochman, Mi Lei

Published Mar 4, 2021• 0 citations
Publisher

Abstract

Optical quantum networks for distributing entanglement between quantum machines will enable distributed quantum computing, secure communications and new sensing methods. These networks will contain quantum transducers for connecting computing qubits to travelling optical photon qubits, and quantum repeater links for distributing entanglement at long distances. In this talk I present implementations of quantum hardware for repeaters and transducers using nano-photonics and rare-earth ions, like ytterbium and erbium, exhibiting highly coherent optical and spin transitions in a solid-state environment. In particular, i discuss optically addressable single quantum bits with single shot readout based on ytterbium 171 atoms, and on-chip storage and processing of photons using erbium ensembles coupled to silicon photonics.

DOI
10.1117/12.2581709

Related papers

Towards quantum networks with single rare-earth ions in nanophotonic cavities

Andrei Faraon, Andrei Ruskuc, Chun Ju Wu +6 more

Quantum optical networks will enable distribution of quantum entanglement at long distances, with applications including interconnects between future quantum computers and secure quantum communications. I will present our recent work on developing quantum networking components based on rare-earth ions such as single optically addressable quantum bits based on ytterbium 171 in yttrium orthovanadate, microwave to optical transducers based on erbium doped crystals coupled to microwave and optical resonators, and on-chip telecom optical quantum memories.

Photonic and Phononic Properties of Engineered Nanostructures•Mar 4, 2022•0 citations

Quantum nano-photonic devices based on rare-earth ions (Conference Presentation)

Andrei Faraon

I present quantum nano-photonic devices based on nanophotonic resonators coupled to rare-earth-ions in crystals. The rare-earth ions exhibit long coherence times on optical transitions, which makes them suitable for optical quantum memories. We demonstrate a high-fidelity nanophotonic quantum memory based on a mesoscopic rare-earth ensemble coupled to a photonic crystal cavity. The nanocavity enables >95% spin polarization for efficient initialization of the atomic frequency comb memory, and time-bin-selective readout via enhanced optical Stark shift of the comb frequencies. Besides ensemble memories, single rare-earth-ions coupled to nano-resonators can be used as single optically addressable quantum bits where the quantum state is mapped on their Zeeman or hyperfine levels with long coherence time. Our solid-state nano-photonic quantum light-matter interfaces can be integrated with other chip-scale photon source and detector devices for multiplexed quantum and classical information processing at the nodes of quantum networks.

Quantum Photonic Devices•Sep 18, 2018•0 citations

Quantum nanophotonic devices based on rare-earth ions (Conference Presentation)

Andrei Faraon

In this talk I give an overview of our recent work on quantum nano-photonic devices based on rare-earth ions. The rare-earth ions exhibit excellent optical and spin coherence properties when embedded in nano-photonic devices. This enables on-chip optical quantum memories, single rare-earth-ion optically addressable quantum bits, and devices for quantum transduction. I will focus on our recent results based on ytterbium 171 in yttrium orthovanadate.

Photonic and Phononic Properties of Engineered Nanostructures•Mar 8, 2019•0 citations

Quantum nanophotonic devices based on rare-earth-doped crystals (Conference Presentation)

Andrei Faraon, Tian Zhong, Jonathan M. Kindem +4 more

Quantum light-matter interfaces that reversibly map the quantum state of photons onto the quantum states of atoms, are essential components in the quantum engineering toolbox with applications in quantum communication, computing, and quantum-enabled sensing. In this talk I present our progress towards developing on-chip quantum light-matter interfaces based on nanophotonic resonators fabricated in rare-earth-doped crystals known to exhibit the longest optical and spin coherence times in the solid state. We recently demonstrated coherent control of neodymium (Nd3+) ions coupled to yttrium orthosilicate Y2SiO5 (YSO) photonic crystal nano-beam resonator. The coupling of the Nd3+ 883 nm 4I9/2-4F3/2 transition to the nano-resonator results in a 40 fold enhancement of the transition rate (Purcell effect), and increased optical absorption (~80%) - adequate for realizing efficient optical quantum memories via cavity impedance matching. Optical coherence times T2 up to 100 μs with low spectral diffusion were measured for ions embedded in photonic crystals, which are comparable to those observed in unprocessed bulk samples. This indicates that the remarkable coherence properties of REIs are preserved during nanofabrication process. Multi-temporal mode photon storage using stimulated photon echo and atomic frequency comb (AFC) protocols were implemented in these nano-resonators. Our current technology can be readily transferred to Erbium (Er) doped YSO devices, therefore opening the possibility of efficient on-chip optical quantum memory at 1.5 μm telecom wavelength. Integration with superconducting qubits can lead to devices for reversible quantum conversion of optical photons to microwave photons.

•Apr 28, 2017•0 citations

A heteroepitaxial architecture for rare-earth quantum light-matter interconnects

Tian Zhong

Quantum nanophotonics interfacing optical photons with coherent atomic spins have the potential to revolutionize secure communications, ultra-scale sensing, distributed quantum computing, and enhanced metrology, but currently lack scalable material and device platform necessary for building robust quantum light-matter interfaces. The trivalent rare-earth ion such as erbium (Er3+) is a promising candidate for quantum interfaces because of its narrow optical transition as well as a long spin coherence time. Here, we present an epitaxial Er3+:Y2O3 on silicon platform for scalable quantum light-matter interconnect, enabling efficient spin-photon interfaces based on individual rare-earth qubits and quantum transduction via ensembles of ions.

Quantum Nanophotonic Materials, Devices, and Systems•Jul 30, 2021•0 citations

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

Mehmet T. Uysal, Łukasz Dusanowski, Haitong Xu +5 more

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 − μ m 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.

arXiv:2406.06515•Physical Review X•Mar 26, 2025•36 citations
Optical quantum networks for distributing entanglement between quantum machines will enable distributed quantum computing, secure communications and new sensing methods. These networks will contain quantum transducers for connecting computing qubits to travelling optical photon qubits, and quantum repeater links for distributing entanglement at long distances. In this talk I present implementations of quantum hardware for repeaters and transducers using nano-photonics and rare-earth ions, like ytterbium and erbium, exhibiting highly coherent optical and spin transitions in a solid-state environment. In particular, i discuss optically addressable single quantum bits with single shot readout based on ytterbium 171 atoms, and on-chip storage and processing of photons using erbium ensembles coupled to silicon photonics.
Quantum optical networks will enable distribution of quantum entanglement at long distances, with applications including interconnects between future quantum computers and secure quantum communications. I will present our recent work on developing quantum networking components based on rare-earth ions such as single optically addressable quantum bits based on ytterbium 171 in yttrium orthovanadate, microwave to optical transducers based on erbium doped crystals coupled to microwave and optical resonators, and on-chip telecom optical quantum memories.
I present quantum nano-photonic devices based on nanophotonic resonators coupled to rare-earth-ions in crystals. The rare-earth ions exhibit long coherence times on optical transitions, which makes them suitable for optical quantum memories. We demonstrate a high-fidelity nanophotonic quantum memory based on a mesoscopic rare-earth ensemble coupled to a photonic crystal cavity. The nanocavity enables >95% spin polarization for efficient initialization of the atomic frequency comb memory, and time-bin-selective readout via enhanced optical Stark shift of the comb frequencies. Besides ensemble memories, single rare-earth-ions coupled to nano-resonators can be used as single optically addressable quantum bits where the quantum state is mapped on their Zeeman or hyperfine levels with long coherence time. Our solid-state nano-photonic quantum light-matter interfaces can be integrated with other chip-scale photon source and detector devices for multiplexed quantum and classical information processing at the nodes of quantum networks.
Quantum light-matter interfaces that reversibly map the quantum state of photons onto the quantum states of atoms, are essential components in the quantum engineering toolbox with applications in quantum communication, computing, and quantum-enabled sensing. In this talk I present our progress towards developing on-chip quantum light-matter interfaces based on nanophotonic resonators fabricated in rare-earth-doped crystals known to exhibit the longest optical and spin coherence times in the solid state. We recently demonstrated coherent control of neodymium (Nd3+) ions coupled to yttrium orthosilicate Y2SiO5 (YSO) photonic crystal nano-beam resonator. The coupling of the Nd3+ 883 nm 4I9/2-4F3/2 transition to the nano-resonator results in a 40 fold enhancement of the transition rate (Purcell effect), and increased optical absorption (~80%) - adequate for realizing efficient optical quantum memories via cavity impedance matching. Optical coherence times T2 up to 100 μs with low spectral diffusion were measured for ions embedded in photonic crystals, which are comparable to those observed in unprocessed bulk samples. This indicates that the remarkable coherence properties of REIs are preserved during nanofabrication process. Multi-temporal mode photon storage using stimulated photon echo and atomic frequency comb (AFC) protocols were implemented in these nano-resonators. Our current technology can be readily transferred to Erbium (Er) doped YSO devices, therefore opening the possibility of efficient on-chip optical quantum memory at 1.5 μm telecom wavelength. Integration with superconducting qubits can lead to devices for reversible quantum conversion of optical photons to microwave photons.
Quantum nanophotonics interfacing optical photons with coherent atomic spins have the potential to revolutionize secure communications, ultra-scale sensing, distributed quantum computing, and enhanced metrology, but currently lack scalable material and device platform necessary for building robust quantum light-matter interfaces. The trivalent rare-earth ion such as erbium (Er3+) is a promising candidate for quantum interfaces because of its narrow optical transition as well as a long spin coherence time. Here, we present an epitaxial Er3+:Y2O3 on silicon platform for scalable quantum light-matter interconnect, enabling efficient spin-photon interfaces based on individual rare-earth qubits and quantum transduction via ensembles of ions.
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 − μ m 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.