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:1012.4387 · Physical Review Letters

Free-Space Lossless State Detection of a Single Trapped Atom

Andreas Fuhrmanek, Ronan Bourgain, Yvan R. P. Sortais, Antoine Browaeys

Published Mar 31, 2011• 92 citations
arXivHTMLPDF

Abstract

We demonstrate the lossless state-selective detection of a single rubidium 87 atom trapped in an optical tweezer. This detection is analogous to the one used on trapped ions. After preparation in either a dark or a bright state, we probe the atom internal state by sending laser light that couples an excited state to the bright state only. The laser-induced fluorescence is collected by a high numerical aperture lens. The single-shot fidelity of the detection is 98.6±0.2% and is presently limited by the dark count noise of the detector. The simplicity of this method opens new perspectives in view of applications to quantum manipulations of neutral atoms.

DOI
10.1103/physrevlett.106.133003

Related papers

Lossless State Detection of Single Neutral Atoms

Joerg Bochmann, Martin Mücke, Conrad Guhl +3 more

We introduce lossless state detection of trapped neutral atoms based on cavity-enhanced fluorescence. In an experiment with a single 87Rb atom, a hyperfine-state-detection fidelity of 99.4% is achieved in 85 μs. The quantum bit is interrogated many hundreds of times without loss of the atom while a result is obtained in every readout attempt. The fidelity proves robust against atomic frequency shifts induced by the trapping potential. Our scheme does not require strong coupling between the atom and cavity and can be generalized to other systems with an optically accessible quantum bit.

arXiv:1002.2918•Physical Review Letters•May 20, 2010•98 citations

Diffraction-limited optics for single-atom manipulation

Yvan R. P. Sortais, H. Marion, Charles Tuchendler +8 more

We present an optical system designed to capture and observe a single neutral atom in an optical dipole trap, created by focusing a laser beam using a large-numerical-aperture $(\mathrm{NA}=0.5)$ aspheric lens. We experimentally evaluate the performance of the optical system and show that it is diffraction limited over a broad spectral range $(\ensuremath{\sim}200\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ with a large transverse field $(\ifmmode\pm\else\textpm\fi{}25\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m})$. The optical tweezer created at the focal point of the lens is able to trap single atoms of $^{87}\mathrm{Rb}$ and to detect them individually with a large collection efficiency. We measure the oscillation frequency of the atom in the dipole trap and use this value as an independent determination of the waist of the optical tweezer. Finally, we produce with the same lens two dipole traps separated by $2.2\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$ and show that the imaging system can resolve the two atoms.

arXiv:quant-ph/0610071•Physical Review A•Jan 8, 2007•119 citations

Bichromatic Imaging of Single Molecules in an Optical Tweezer Array

Connor M. Holland, Yukai Lu, Lawrence W. Cheuk

We report on a novel bichromatic fluorescent imaging scheme for background-free detection of single CaF molecules trapped in an optical tweezer array. By collecting fluorescence on one optical transition while using another for laser cooling, we achieve an imaging fidelity of 97.7(2)% and a nondestructive detection fidelity of 95.5(6)%. Notably, these fidelities are achieved with a modest photon budget, suggesting that the method could be extended to more complex laser-coolable molecules with less favorable optical cycling properties. We also report on a framework and new methods to characterize various loss mechanisms that occur generally during fluorescent detection of trapped molecules, including two-photon decay and admixtures of higher excited states that are induced by the trapping light. In particular, we develop a novel method to dispersively measure transition matrix elements between electronically excited states. The method could also be used to measure arbitrarily small Franck-Condon factors between electronically excited states, which could significantly aid in ongoing efforts to laser cool complex polyatomic molecules.

arXiv:2208.12159•Physical Review Letters•Aug 4, 2023•16 citations

High-fidelity low-loss state detection of alkali-metal atoms in optical tweezer traps

Matthew N. H. Chow, Bethany Little, Yuan‐Yu Jau

We demonstrate the discrimination of ground-state hyperfine manifolds of a cesium atom in an optical tweezer using a simple probe beam with $99.{91}_{\ensuremath{-}0.02}^{+0.02}$% detection fidelity and 0.9(2)% detection-driven loss of bright-state atoms. Our detection infidelity of $0.{09}_{\ensuremath{-}0.02}^{+0.02}$% is an order of magnitude better than previously published low-loss readout results for alkali-metal atoms in optical tweezers. We achieve these results by identifying and mitigating an extra depumping mechanism due to stimulated Raman transitions induced by trap light in the presence of probe light. In this work, complex optical systems and stringent vacuum pressures are not required, enabling straightforward adoption of our techniques on contemporary experiments.

arXiv:2206.00144•Physical Review A•Sep 7, 2023•18 citations

Trapping and detection of single rubidium atoms in an optical dipole trap using a long-focus objective lens

Ilya I. Beterov, Elena A. Yakshina, Denis B. Tretyakov +7 more

Abstract The trapping of single atoms in optical dipole traps is widely used in experiments on the implementation of quantum processors based on neutral atoms, and studying interatomic interactions. Typically, such experiments employ lenses with a large numerical aperture (NA > 0.5), highly sensitive EMCCD cameras, or photon counters. In this work, we demonstrate trapping and detection of single rubidium atoms using a long-focus objective lens with a numerical aperture NA = 0.172 and a FLir Tau CNV sCMOS camera.

Quantum Electronics•Jun 1, 2020•9 citations

Atom--photon Entanglement with a Single Trapped Cesium Atom

H. Hwang, J. Moon, F. Herzallah +3 more

We demonstrate atom--photon entanglement using a single cesium atom trapped in an optical tweezer. Entanglement is generated by resonant excitation and subsequent spontaneous decay, which entangles the atomic Zeeman state with photon polarization. The photon is collected with a high numerical aperture objective (NA = 0.55) and coupled into a single-mode fiber, enabling atom photon measurements and measurement of the Bell-state fidelity. We obtain raw entanglement fidelity of ${\mathcal F} = 0.942(16)$ and inferred fidelity of ${\mathcal F}_{\rm inf} = 0.962(26)$ after correcting independently characterized atom measurement errors. Compared with related free-space experiments using $^{87}$Rb, the multilevel structure of the relevant excited state in $^{133}$Cs requires the use of a single short excitation pulse in each entanglement attempt in order to suppress unwanted re-excitation. These results establish a free-space Cs atom--photon interface and provide a step toward dual-species Rb--Cs quantum networking.

quant-pharXiv:2605.28968•Physical Review Letters•May 29, 2026•0 citations
We demonstrate the lossless state-selective detection of a single rubidium 87 atom trapped in an optical tweezer. This detection is analogous to the one used on trapped ions. After preparation in either a dark or a bright state, we probe the atom internal state by sending laser light that couples an excited state to the bright state only. The laser-induced fluorescence is collected by a high numerical aperture lens. The single-shot fidelity of the detection is 98.6±0.2% and is presently limited by the dark count noise of the detector. The simplicity of this method opens new perspectives in view of applications to quantum manipulations of neutral atoms.
We introduce lossless state detection of trapped neutral atoms based on cavity-enhanced fluorescence. In an experiment with a single 87Rb atom, a hyperfine-state-detection fidelity of 99.4% is achieved in 85 μs. The quantum bit is interrogated many hundreds of times without loss of the atom while a result is obtained in every readout attempt. The fidelity proves robust against atomic frequency shifts induced by the trapping potential. Our scheme does not require strong coupling between the atom and cavity and can be generalized to other systems with an optically accessible quantum bit.
We present an optical system designed to capture and observe a single neutral atom in an optical dipole trap, created by focusing a laser beam using a large-numerical-aperture (NA=0.5)(\mathrm{NA}=0.5)(NA=0.5) aspheric lens. We experimentally evaluate the performance of the optical system and show that it is diffraction limited over a broad spectral range $(\ensuremath{\sim}200\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ with a large transverse field $(\ifmmode\pm\else\textpm\fi{}25\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m})$. The optical tweezer created at the focal point of the lens is able to trap single atoms of 87Rb^{87}\mathrm{Rb}87Rb and to detect them individually with a large collection efficiency. We measure the oscillation frequency of the atom in the dipole trap and use this value as an independent determination of the waist of the optical tweezer. Finally, we produce with the same lens two dipole traps separated by $2.2\phantom{\rule{0.3em}{0ex}}\ensuremath{\mu}\mathrm{m}$ and show that the imaging system can resolve the two atoms.
We report on a novel bichromatic fluorescent imaging scheme for background-free detection of single CaF molecules trapped in an optical tweezer array. By collecting fluorescence on one optical transition while using another for laser cooling, we achieve an imaging fidelity of 97.7(2)% and a nondestructive detection fidelity of 95.5(6)%. Notably, these fidelities are achieved with a modest photon budget, suggesting that the method could be extended to more complex laser-coolable molecules with less favorable optical cycling properties. We also report on a framework and new methods to characterize various loss mechanisms that occur generally during fluorescent detection of trapped molecules, including two-photon decay and admixtures of higher excited states that are induced by the trapping light. In particular, we develop a novel method to dispersively measure transition matrix elements between electronically excited states. The method could also be used to measure arbitrarily small Franck-Condon factors between electronically excited states, which could significantly aid in ongoing efforts to laser cool complex polyatomic molecules.
We demonstrate the discrimination of ground-state hyperfine manifolds of a cesium atom in an optical tweezer using a simple probe beam with $99.{91}_{\ensuremath{-}0.02}^{+0.02}$% detection fidelity and 0.9(2)% detection-driven loss of bright-state atoms. Our detection infidelity of $0.{09}_{\ensuremath{-}0.02}^{+0.02}$% is an order of magnitude better than previously published low-loss readout results for alkali-metal atoms in optical tweezers. We achieve these results by identifying and mitigating an extra depumping mechanism due to stimulated Raman transitions induced by trap light in the presence of probe light. In this work, complex optical systems and stringent vacuum pressures are not required, enabling straightforward adoption of our techniques on contemporary experiments.
Abstract The trapping of single atoms in optical dipole traps is widely used in experiments on the implementation of quantum processors based on neutral atoms, and studying interatomic interactions. Typically, such experiments employ lenses with a large numerical aperture (NA > 0.5), highly sensitive EMCCD cameras, or photon counters. In this work, we demonstrate trapping and detection of single rubidium atoms using a long-focus objective lens with a numerical aperture NA = 0.172 and a FLir Tau CNV sCMOS camera.
We demonstrate atom--photon entanglement using a single cesium atom trapped in an optical tweezer. Entanglement is generated by resonant excitation and subsequent spontaneous decay, which entangles the atomic Zeeman state with photon polarization. The photon is collected with a high numerical aperture objective (NA = 0.55) and coupled into a single-mode fiber, enabling atom photon measurements and measurement of the Bell-state fidelity. We obtain raw entanglement fidelity of F=0.942(16){\mathcal F} = 0.942(16)F=0.942(16) and inferred fidelity of Finf=0.962(26){\mathcal F}_{\rm inf} = 0.962(26)Finf​=0.962(26) after correcting independently characterized atom measurement errors. Compared with related free-space experiments using 87^{87}87Rb, the multilevel structure of the relevant excited state in 133^{133}133Cs requires the use of a single short excitation pulse in each entanglement attempt in order to suppress unwanted re-excitation. These results establish a free-space Cs atom--photon interface and provide a step toward dual-species Rb--Cs quantum networking.