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:2607.11282 · Physical Review A

Barium-based Rydberg atom quantum technologies with long Rydberg coherence

Xiao-Feng Shi

quant-phSubmitted Jul 13, 2026• Announced Jul 14, 2026• 2 citations
arXivHTMLPDF

Abstract

The short Doppler-limited coherence time of the laser-excited Rydberg state, usually orders of magnitude shorter than the lifetime of the Rydberg state, hinders the Rydberg-mediated quantum technologies. Here, we show that a 649~nm~$-$~658~nm two-photon excitation of the $6sng~^1G_4$ Rydberg state from a long-lived d-orbital clock state of barium can be achieved with a two-photon wavevector that is tiny, which effectively removes the Doppler-limited decoherence. Moreover, the $6sng~^1G_4$ Rydberg state has strong dipole-dipole interaction due to small Förster defect with nearby Rydberg states and possesses long radiative lifetime. These can benefit quantum computing based on individually trapped neutral atoms, and can enable long-lived Rydberg polaritons in atomic media, which brings fresh opportunities in all-optical quantum information.

Journal reference
Phys. Rev. A 112, 042401 (2025)
DOI
10.1103/bbv3-d4ch
Comments
14 pages, 6 figures

Related papers

Laser Trapping of Circular Rydberg Atoms

Rodrigo G. Cortiñas, Maxime Favier, Brice Ravon +5 more

Rydberg atoms are remarkable tools for quantum simulation and computation. They are the focus of an intense experimental activity, mainly based on low-angular-momentum Rydberg states. Unfortunately, atomic motion and levels lifetime limit the experimental timescale to about 100 μs. Here, we demonstrate two-dimensional laser trapping of long-lived circular Rydberg states for up to 10 ms. Our method is very general and opens many opportunities for quantum technologies with Rydberg atoms. The 10 ms trapping time corresponds to thousands of interaction cycles in a circular-state-based quantum simulator. It is also promising for quantum metrology and quantum information with Rydberg atoms, by bringing atom-field interaction times into unprecedented regimes.

arXiv:1911.02316•Physical Review Letters•Mar 23, 2020•62 citations

Coherence enhancement of Rydberg polaritons

Xiao-Feng Shi, Yan Lu, Yuechun Jiao +1 more

Quantum nonlinear optics by Rydberg polaritons can enable single-photon transistor and switch, single-photon source, and deterministic quantum information processing. A major hindrance in this study is the fast motional decoherence. Here, we devise a scheme to significantly enhance the coherence of Rydberg polariton by letting the atoms {\it remember} their velocities, or, alternatively, by {\it changing} the phase of Rydberg polariton according to its storage time. After the Rydberg polariton is prepared with a Rydberg state $|r_1\rangle$, i.e., during the storage time, two laser fields induce a transition between $|r_1\rangle$ and a nearby Rydberg state $|r_2\rangle$ via a low-lying intermediate state $\lvert f\rangle$ which is largely detuned. In particular, we find that either a $2π\mathbb{N}$ protocol, a $π$-wait-$π$ protocol, or a wait-$π$ protocol, along with an appropriate choice of $\lvert f\rangle$ can lead to a phase-coherent Rydberg polariton upon its retrieval. Importantly, the coherent transition between $|r_1\rangle$ and $|r_2\rangle$ ensures that the Rydberg polariton can block the Rydberg excitation of nearby atoms as in usual applications of Rydberg polaritons. Numerics show that the theory can nearly completely eliminate the motional dephasing, leaving Rydberg-state decay as the only fundamental channel of decoherence. This sheds light on a broad application of Rydberg-mediated quantum nonlinear optics.

physics.atom-phCross-listedarXiv:2607.12513•Physical Review Applied•Jul 15, 2026•1 citation

Rydberg Atoms and Strongly Coupled Atom-Light Systems

Zihan Zhang

Since the discovery of the Rydberg atom in 1885, research on the Rydberg atom has presented numerous discoveries about the Rydberg atom. As the atoms has valence electron in a high principal quantum number state, Rydberg atoms can interact with each other in a unique way, such as dipole-dipole interactions, Rydberg blockade and anti-blockade. To reach the Rydberg state, it is usually necessary to use a laser to excite the atoms from their ground state. Due to the special characteristics about Rydberg atoms as well as their interactions, it has demonstrated promising of application in different fields, for example, quantum computing and quantum information, as well as nonlinear optics and photonics. However, due to the technical limitations, the demand of deterministic atoms sources and the effect of blackbody radiation are still hindering the research relative to Rydberg atoms. For future study relative to Rydberg atoms, the additions with laser-trapping could be beneficial for fields like quantum electro dynamics and localized electromagnetic field probing.

Transactions on Computer Science and Intelligent Systems Research•Nov 25, 2024•0 citations

Long-Lived Circular Rydberg Qubits of Alkaline-Earth Atoms in Optical Tweezers

Christian Hölzl, Aaron Götzelmann, Einius Pultinevicius +2 more

Coherence time and gate fidelities in Rydberg atom quantum simulators and computers are fundamentally limited by the Rydberg state lifetime. Circular Rydberg states are highly promising candidates to overcome this limitation by orders of magnitude, as they can be effectively protected from decay due to their maximum angular momentum. We report the first realization of alkaline-earth circular Rydberg atoms trapped in optical tweezers, which provide unique and novel control possibilities due to the optically active ionic core. Specifically, we demonstrate creation of very high- n ( n = 79 ) circular states of Sr 88 . We measure lifetimes as long as 2.55 ms at room temperature, which are achieved via cavity-assisted suppression of black-body radiation. We show coherent control of a microwave qubit encoded in circular states of nearby manifolds, and characterize the qubit coherence time via Ramsey and spin-echo spectroscopy. Finally, circular-state tweezer trapping exploiting the Sr + core polarizability is quantified via measurements of the trap-induced light shift on the qubit. Our work opens routes for quantum simulations with circular Rydberg states of divalent atoms, exploiting the emergent toolbox associated with the optically active core ion. Published by the American Physical Society 2024

arXiv:2401.10625•Physical Review X•May 3, 2024•41 citations

Quantum information with Rydberg atoms

Mark E. Saffman, Thad G Walker, Klaus Mølmer

Rydberg atoms with principal quantum number $n⪢1$ have exaggerated atomic properties including dipole-dipole interactions that scale as ${n}^{4}$ and radiative lifetimes that scale as ${n}^{3}$. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom qubits. The availability of a strong long-range interaction that can be coherently turned on and off is an enabling resource for a wide range of quantum information tasks stretching far beyond the original gate proposal. Rydberg enabled capabilities include long-range two-qubit gates, collective encoding of multiqubit registers, implementation of robust light-atom quantum interfaces, and the potential for simulating quantum many-body physics. The advances of the last decade are reviewed, covering both theoretical and experimental aspects of Rydberg-mediated quantum information processing.

arXiv:0909.4777•Reviews of Modern Physics•Aug 18, 2010•2,838 citations

Long-lived giant circular Rydberg atoms at room temperature

Einius Pultinevicius, Aaron Götzelmann, Fabian Thielemann +2 more

Stability achieved by large angular momentum is ubiquitous in nature, with examples ranging from classical mechanics, over optics and chemistry, to nuclear physics. In atoms, angular momentum can protect excited electronic orbitals from decay due to selection rules. This manifests spectacularly in highly excited Rydberg states. Low angular momentum Rydberg states are at the heart of recent breakthroughs in quantum computing, simulation and sensing with neutral atoms. For these applications the lifetime of the Rydberg levels sets fundamental limits for gate fidelities, coherence times, or spectroscopic precision. The quest for longer Rydberg state lifetimes has motivated the generation, coherent control and trapping of circular Rydberg atoms, which are characterized by the maximally allowed electron orbital momentum and were key to seminal experiments with single atoms and photons. Here, we report the observation of individually trapped circular Rydberg atoms with lifetimes of more than 10 milliseconds, two orders of magnitude longer-lived than the established low angular momentum orbitals. This is achieved via Purcell suppression of blackbody modes at room temperature. We coherently control individual circular Rydberg levels at so far elusive principal quantum numbers of up to n = 103, and observe tweezer trapping of the Rydberg atoms on the hundred millisecond scale. Our results pave the way for quantum information processing and sensing utilizing the combination of extreme lifetimes and giant Rydberg blockade.

•Jan 1, 2026•0 citations
The short Doppler-limited coherence time of the laser-excited Rydberg state, usually orders of magnitude shorter than the lifetime of the Rydberg state, hinders the Rydberg-mediated quantum technologies. Here, we show that a 649nm−-−658nm two-photon excitation of the 6sng 1G46sng~^1G_46sng 1G4​ Rydberg state from a long-lived d-orbital clock state of barium can be achieved with a two-photon wavevector that is tiny, which effectively removes the Doppler-limited decoherence. Moreover, the 6sng 1G46sng~^1G_46sng 1G4​ Rydberg state has strong dipole-dipole interaction due to small Förster defect with nearby Rydberg states and possesses long radiative lifetime. These can benefit quantum computing based on individually trapped neutral atoms, and can enable long-lived Rydberg polaritons in atomic media, which brings fresh opportunities in all-optical quantum information.
Rydberg atoms are remarkable tools for quantum simulation and computation. They are the focus of an intense experimental activity, mainly based on low-angular-momentum Rydberg states. Unfortunately, atomic motion and levels lifetime limit the experimental timescale to about 100 μs. Here, we demonstrate two-dimensional laser trapping of long-lived circular Rydberg states for up to 10 ms. Our method is very general and opens many opportunities for quantum technologies with Rydberg atoms. The 10 ms trapping time corresponds to thousands of interaction cycles in a circular-state-based quantum simulator. It is also promising for quantum metrology and quantum information with Rydberg atoms, by bringing atom-field interaction times into unprecedented regimes.
Quantum nonlinear optics by Rydberg polaritons can enable single-photon transistor and switch, single-photon source, and deterministic quantum information processing. A major hindrance in this study is the fast motional decoherence. Here, we devise a scheme to significantly enhance the coherence of Rydberg polariton by letting the atoms {\it remember} their velocities, or, alternatively, by {\it changing} the phase of Rydberg polariton according to its storage time. After the Rydberg polariton is prepared with a Rydberg state ∣r1⟩|r_1\rangle∣r1​⟩, i.e., during the storage time, two laser fields induce a transition between ∣r1⟩|r_1\rangle∣r1​⟩ and a nearby Rydberg state ∣r2⟩|r_2\rangle∣r2​⟩ via a low-lying intermediate state ∣f⟩\lvert f\rangle∣f⟩ which is largely detuned. In particular, we find that either a 2πN2π\mathbb{N}2πN protocol, a πππ-wait-πππ protocol, or a wait-πππ protocol, along with an appropriate choice of ∣f⟩\lvert f\rangle∣f⟩ can lead to a phase-coherent Rydberg polariton upon its retrieval. Importantly, the coherent transition between ∣r1⟩|r_1\rangle∣r1​⟩ and ∣r2⟩|r_2\rangle∣r2​⟩ ensures that the Rydberg polariton can block the Rydberg excitation of nearby atoms as in usual applications of Rydberg polaritons. Numerics show that the theory can nearly completely eliminate the motional dephasing, leaving Rydberg-state decay as the only fundamental channel of decoherence. This sheds light on a broad application of Rydberg-mediated quantum nonlinear optics.
Since the discovery of the Rydberg atom in 1885, research on the Rydberg atom has presented numerous discoveries about the Rydberg atom. As the atoms has valence electron in a high principal quantum number state, Rydberg atoms can interact with each other in a unique way, such as dipole-dipole interactions, Rydberg blockade and anti-blockade. To reach the Rydberg state, it is usually necessary to use a laser to excite the atoms from their ground state. Due to the special characteristics about Rydberg atoms as well as their interactions, it has demonstrated promising of application in different fields, for example, quantum computing and quantum information, as well as nonlinear optics and photonics. However, due to the technical limitations, the demand of deterministic atoms sources and the effect of blackbody radiation are still hindering the research relative to Rydberg atoms. For future study relative to Rydberg atoms, the additions with laser-trapping could be beneficial for fields like quantum electro dynamics and localized electromagnetic field probing.
Coherence time and gate fidelities in Rydberg atom quantum simulators and computers are fundamentally limited by the Rydberg state lifetime. Circular Rydberg states are highly promising candidates to overcome this limitation by orders of magnitude, as they can be effectively protected from decay due to their maximum angular momentum. We report the first realization of alkaline-earth circular Rydberg atoms trapped in optical tweezers, which provide unique and novel control possibilities due to the optically active ionic core. Specifically, we demonstrate creation of very high- n ( n = 79 ) circular states of Sr 88 . We measure lifetimes as long as 2.55 ms at room temperature, which are achieved via cavity-assisted suppression of black-body radiation. We show coherent control of a microwave qubit encoded in circular states of nearby manifolds, and characterize the qubit coherence time via Ramsey and spin-echo spectroscopy. Finally, circular-state tweezer trapping exploiting the Sr + core polarizability is quantified via measurements of the trap-induced light shift on the qubit. Our work opens routes for quantum simulations with circular Rydberg states of divalent atoms, exploiting the emergent toolbox associated with the optically active core ion. Published by the American Physical Society 2024
Rydberg atoms with principal quantum number n⪢1n⪢1n⪢1 have exaggerated atomic properties including dipole-dipole interactions that scale as n4{n}^{4}n4 and radiative lifetimes that scale as n3{n}^{3}n3. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom qubits. The availability of a strong long-range interaction that can be coherently turned on and off is an enabling resource for a wide range of quantum information tasks stretching far beyond the original gate proposal. Rydberg enabled capabilities include long-range two-qubit gates, collective encoding of multiqubit registers, implementation of robust light-atom quantum interfaces, and the potential for simulating quantum many-body physics. The advances of the last decade are reviewed, covering both theoretical and experimental aspects of Rydberg-mediated quantum information processing.
Stability achieved by large angular momentum is ubiquitous in nature, with examples ranging from classical mechanics, over optics and chemistry, to nuclear physics. In atoms, angular momentum can protect excited electronic orbitals from decay due to selection rules. This manifests spectacularly in highly excited Rydberg states. Low angular momentum Rydberg states are at the heart of recent breakthroughs in quantum computing, simulation and sensing with neutral atoms. For these applications the lifetime of the Rydberg levels sets fundamental limits for gate fidelities, coherence times, or spectroscopic precision. The quest for longer Rydberg state lifetimes has motivated the generation, coherent control and trapping of circular Rydberg atoms, which are characterized by the maximally allowed electron orbital momentum and were key to seminal experiments with single atoms and photons. Here, we report the observation of individually trapped circular Rydberg atoms with lifetimes of more than 10 milliseconds, two orders of magnitude longer-lived than the established low angular momentum orbitals. This is achieved via Purcell suppression of blackbody modes at room temperature. We coherently control individual circular Rydberg levels at so far elusive principal quantum numbers of up to n = 103, and observe tweezer trapping of the Rydberg atoms on the hundred millisecond scale. Our results pave the way for quantum information processing and sensing utilizing the combination of extreme lifetimes and giant Rydberg blockade.