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

arXiv:2305.01216 · Chinese Physics Letters

Stark Tuning of Telecom Single-Photon Emitters Based on a Single Er3+

Jian-Yin Huang, Peng-Jun Liang, Liang Zheng, Pei-Yun Li, You-Zhi Ma, Duan-Chen Liu, Jing-Hui Xie, Zong‐Quan Zhou, Chuan‐Feng Li, Guang‐Can Guo

Published May 27, 2023• 19 citations
arXivHTMLPDF

Abstract

The implementation of scalable quantum networks requires photons at the telecom band and long-lived spin coherence. The single Er3+ in solid-state hosts is an important candidate that fulfills these critical requirements simultaneously. However, to entangle distant Er3+ ions through photonic connections, the emission frequency of individual Er3+ in solid-state matrix must be the same, which is challenging because the emission frequency of Er3+ depends on its local environment. Herein, we propose and experimentally demonstrate the Stark tuning of the emission frequency of a single Er3+ in a Y2SiO5 crystal by employing electrodes interfaced with a silicon photonic crystal cavity. We obtain a Stark shift of 182.9±0.8 MHz, which is approximately 27 times of the optical emission linewidth, demonstrating promising applications in tuning the emission frequency of independent Er3+ into the same spectral channels. Our results provide a useful solution for construction of scalable quantum networks based on single Er3+ and a universal tool for tuning emission of individual rare-earth ions.

DOI
10.1088/0256-307x/40/7/070301

Related papers

Frequency Tunable, Cavity-Enhanced Single Erbium Quantum Emitter in the Telecom Band

Yong Hui Yu, Dorian Oser, Gaia Da Prato +7 more

Single quantum emitters embedded in solid-state hosts are an ideal platform for realizing quantum information processors and quantum network nodes. Among the currently investigated candidates, Er^{3+} ions are particularly appealing due to their 1.5 μm optical transition in the telecom band as well as their long spin coherence times. However, the long lifetimes of the excited state-generally in excess of 1 ms-along with the inhomogeneous broadening of the optical transition result in significant challenges. Photon emission rates are prohibitively small, and different emitters generally create photons with distinct spectra, thereby preventing multiphoton interference-a requirement for building large-scale, multinode quantum networks. Here we solve this challenge by demonstrating for the first time linear Stark tuning of the emission frequency of a single Er^{3+} ion. Our ions are embedded in a lithium niobate crystal and couple evanescently to a silicon nanophotonic crystal cavity that provides a strong increase of the measured decay rate. By applying an electric field along the crystal c axis, we achieve a Stark tuning greater than the ion's linewidth without changing the single-photon emission statistics of the ion. These results are a key step towards rare earth ion-based quantum networks.

arXiv:2304.14685•Physical Review Letters•Oct 23, 2023•35 citations

Spectral tuning of single T centres by the Stark effect

Michael Dobinson, Felix Hufnagel, Simon A. Meynell +8 more

Among the many solid-state emitters being explored for scalable quantum technologies, the silicon T centre is a leading candidate offering long-lived spin qubits, a telecommunications-band spin-photon interface, and integration with on-chip photonic circuits. However, nanophotonic integration broadens both the inhomogeneous spectral distribution and individual emitter linewidths. Here, we integrate single T centres into silicon nanophotonic cavities with p-i-n diodes for local electronic control. These devices enable Stark tuning up to 30 GHz, sufficient to bring 55(2)% of on-chip T centres into mutual resonance, and demonstrate tunable lifetime reduction across the cavity resonance. A model of the joint excitation probability shows an orders-of-magnitude increase in entanglement rate by tuning distinct emitters into mutual resonance. Luminescence modulation at high reverse biases reveals a transition to a dark charge state. Finally, bias-induced modulation of the optical transition splitting uncovers a potential mechanism for electrically driven excited-state spin mixing via spin-orbit coupling. Localized and individual spectral tuning increases the yield of performant silicon spin-photon interfaces and the number of devices per chip available for large-scale entanglement and quantum information technologies.

quant-pharXiv:2604.25170•Apr 29, 2026

Enhancing erbium optical emission rate via high-throughput host crystal selection

Gregory D. Grant, Swarnabha Chattaraj, Chelsie Hadley +5 more

Erbium-doped solid-state crystals present an attractive platform for quantum communication, combining the telecom C-band spin–photon interface and long coherence times of erbium (Er3+) with the versatility of solid-state hosts. However, across commonly investigated materials, Er3+ is a “dim” ion, with low optical emission rates of kilohertz at most. This makes implementing quantum information transfer protocols (e.g., quantum teleportation) at usable rates a major challenge. One route to increasing Er3+ radiative rates is by careful selection of crystal hosts: the crystal field around an Er3+ ion may hybridize states of different parity, potentially increasing the radiative rate of its telecom transition. Here, using high-throughput computational methods, the radiative rates of Er3+ embedded in 9215 materials are estimated. The computation shows that careful host selection could increase Er3+ radiative rates by an order of magnitude compared to commonly studied hosts. Calculated results are compared with experimental radiative rates in a subset of materials, finding notable clustering but weak correlation. Nevertheless, the “brightest” candidates combined with suitable nanophotonics engineering could push Er3+-based quantum memories into the megahertz bandwidth regime.

Applied Physics Letters•Sep 7, 2026•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

Towards telecom-compatible quantum nodes using erbium-doped stoichiometric EuCl3 ⋅ 6H2O crystals

Mucheng Guo, Wanting Xiao, Zongfeng Li +7 more

Abstract Doping erbium ions into europium-based hosts offers a promising platform for quantum repeater nodes, combining europium’s exceptional coherence properties for long-term quantum storage with erbium’s microwave compatibility and direct telecom-band emission for efficient optical interfacing. In this work, we investigated erbium-doped EuCl3 · 6H2O stoichiometric crystals as a candidate for such nodes. We demonstrate that erbium doping shifts the optical transition frequencies of nearby Eu3+ ions, producing well resolved satellite lines in the inhomogeneous absorption profile. We experimentally probe the coupling between Er3+ and Eu3+ ions under varying temperature and magnetic field conditions, quantifying the interaction strength, which ranges from tens to hundreds of kilohertz, depending on field orientation, magnitude, and the lattice position of the Eu3+ ions. At 60 mK and a moderate magnetic field of 0.1 T, we observed a strong frozen core effect from Er3+ spins, substantially extending the Eu3+ optical coherence time from 62 us to 162 us, approaching the lifetime limit, and enabling hour-long hyperfine state lifetimes. These results underscore the potential of dual-species rare-earth systems for photonic quantum technologies and highlight their promise for precise quantum control.

npj Quantum Information•Feb 25, 2026•0 citations

Rare-earth ion-integrated silicon photonics for quantum networks

Robert M. Pettit, Ananthesh Sundaresh, Victoria Rosborough +9 more

Rare-earth ion defects in solid-state hosts have emerged as a promising candidate for emissive quantum memories owing to their inherent spin–photon interface and long optical and spin coherence times. Erbium (Er3+) in particular has optical transitions in the C-band making it well suited to the use of existing telecom technology infrastructure. In this work, we present a platform to integrate rare-earth ions into standard silicon photonic circuits. Erbium is co-deposited in CMOS-compatible TiO2 host films onto SOI and patterned into high Purcell factor photonic crystal cavities. Purcell factors in excess of 500 are observed and transient spectral hole burning and photoluminescence excitation scans reveal homogeneous linewidths below 15 MHz. Additionally, we show that photonic wirebonding can provide a solution for low-loss and thermally stable fiber-to-chip coupling.

SPIE Quantum Information Science, Sensing, and Computation•Jun 7, 2024•0 citations
The implementation of scalable quantum networks requires photons at the telecom band and long-lived spin coherence. The single Er3+ in solid-state hosts is an important candidate that fulfills these critical requirements simultaneously. However, to entangle distant Er3+ ions through photonic connections, the emission frequency of individual Er3+ in solid-state matrix must be the same, which is challenging because the emission frequency of Er3+ depends on its local environment. Herein, we propose and experimentally demonstrate the Stark tuning of the emission frequency of a single Er3+ in a Y2SiO5 crystal by employing electrodes interfaced with a silicon photonic crystal cavity. We obtain a Stark shift of 182.9±0.8 MHz, which is approximately 27 times of the optical emission linewidth, demonstrating promising applications in tuning the emission frequency of independent Er3+ into the same spectral channels. Our results provide a useful solution for construction of scalable quantum networks based on single Er3+ and a universal tool for tuning emission of individual rare-earth ions.
Single quantum emitters embedded in solid-state hosts are an ideal platform for realizing quantum information processors and quantum network nodes. Among the currently investigated candidates, Er^{3+} ions are particularly appealing due to their 1.5 μm optical transition in the telecom band as well as their long spin coherence times. However, the long lifetimes of the excited state-generally in excess of 1 ms-along with the inhomogeneous broadening of the optical transition result in significant challenges. Photon emission rates are prohibitively small, and different emitters generally create photons with distinct spectra, thereby preventing multiphoton interference-a requirement for building large-scale, multinode quantum networks. Here we solve this challenge by demonstrating for the first time linear Stark tuning of the emission frequency of a single Er^{3+} ion. Our ions are embedded in a lithium niobate crystal and couple evanescently to a silicon nanophotonic crystal cavity that provides a strong increase of the measured decay rate. By applying an electric field along the crystal c axis, we achieve a Stark tuning greater than the ion's linewidth without changing the single-photon emission statistics of the ion. These results are a key step towards rare earth ion-based quantum networks.
Among the many solid-state emitters being explored for scalable quantum technologies, the silicon T centre is a leading candidate offering long-lived spin qubits, a telecommunications-band spin-photon interface, and integration with on-chip photonic circuits. However, nanophotonic integration broadens both the inhomogeneous spectral distribution and individual emitter linewidths. Here, we integrate single T centres into silicon nanophotonic cavities with p-i-n diodes for local electronic control. These devices enable Stark tuning up to 30 GHz, sufficient to bring 55(2)% of on-chip T centres into mutual resonance, and demonstrate tunable lifetime reduction across the cavity resonance. A model of the joint excitation probability shows an orders-of-magnitude increase in entanglement rate by tuning distinct emitters into mutual resonance. Luminescence modulation at high reverse biases reveals a transition to a dark charge state. Finally, bias-induced modulation of the optical transition splitting uncovers a potential mechanism for electrically driven excited-state spin mixing via spin-orbit coupling. Localized and individual spectral tuning increases the yield of performant silicon spin-photon interfaces and the number of devices per chip available for large-scale entanglement and quantum information technologies.
Erbium-doped solid-state crystals present an attractive platform for quantum communication, combining the telecom C-band spin–photon interface and long coherence times of erbium (Er3+) with the versatility of solid-state hosts. However, across commonly investigated materials, Er3+ is a “dim” ion, with low optical emission rates of kilohertz at most. This makes implementing quantum information transfer protocols (e.g., quantum teleportation) at usable rates a major challenge. One route to increasing Er3+ radiative rates is by careful selection of crystal hosts: the crystal field around an Er3+ ion may hybridize states of different parity, potentially increasing the radiative rate of its telecom transition. Here, using high-throughput computational methods, the radiative rates of Er3+ embedded in 9215 materials are estimated. The computation shows that careful host selection could increase Er3+ radiative rates by an order of magnitude compared to commonly studied hosts. Calculated results are compared with experimental radiative rates in a subset of materials, finding notable clustering but weak correlation. Nevertheless, the “brightest” candidates combined with suitable nanophotonics engineering could push Er3+-based quantum memories into the megahertz bandwidth regime.
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.
Abstract Doping erbium ions into europium-based hosts offers a promising platform for quantum repeater nodes, combining europium’s exceptional coherence properties for long-term quantum storage with erbium’s microwave compatibility and direct telecom-band emission for efficient optical interfacing. In this work, we investigated erbium-doped EuCl3 · 6H2O stoichiometric crystals as a candidate for such nodes. We demonstrate that erbium doping shifts the optical transition frequencies of nearby Eu3+ ions, producing well resolved satellite lines in the inhomogeneous absorption profile. We experimentally probe the coupling between Er3+ and Eu3+ ions under varying temperature and magnetic field conditions, quantifying the interaction strength, which ranges from tens to hundreds of kilohertz, depending on field orientation, magnitude, and the lattice position of the Eu3+ ions. At 60 mK and a moderate magnetic field of 0.1 T, we observed a strong frozen core effect from Er3+ spins, substantially extending the Eu3+ optical coherence time from 62 us to 162 us, approaching the lifetime limit, and enabling hour-long hyperfine state lifetimes. These results underscore the potential of dual-species rare-earth systems for photonic quantum technologies and highlight their promise for precise quantum control.
Rare-earth ion defects in solid-state hosts have emerged as a promising candidate for emissive quantum memories owing to their inherent spin–photon interface and long optical and spin coherence times. Erbium (Er3+) in particular has optical transitions in the C-band making it well suited to the use of existing telecom technology infrastructure. In this work, we present a platform to integrate rare-earth ions into standard silicon photonic circuits. Erbium is co-deposited in CMOS-compatible TiO2 host films onto SOI and patterned into high Purcell factor photonic crystal cavities. Purcell factors in excess of 500 are observed and transient spectral hole burning and photoluminescence excitation scans reveal homogeneous linewidths below 15 MHz. Additionally, we show that photonic wirebonding can provide a solution for low-loss and thermally stable fiber-to-chip coupling.