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

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

Imaging the temperature of trapped ions

B. G. Norton, Erik W. Streed, Andreas Jechow, M. J. Petrasiunas, D. Kielpinski

Published May 1, 2011• 0 citations
Publisher

Abstract

We have realized wavelength scale fluorescence imaging of trapped Yb+ ions on the 370 nm laser cooling transition. We present results for thermometry of laser cooled trapped ions at temperatures on the order of 100 milli-Kelvin with temperature sensitivities on the order of lOmilli-Kelvin. This technique overcomes the sensitivity limitations of fluorescence spectroscopy in this regime.

DOI
10.1109/cleoe.2011.5943296

Related papers

Imaging the Temperature of Laser-Cooled Ions

B. G. Norton, Erik W. Streed, Andreas Jechow +2 more

We demonstrate milli-Kelvin precision thermometry of laser cooled trapped ions using high-resolution imaging. This steady state approach can be used to investigate ion temperatures even when the laser cooling dynamics are highly anisotropic.

•Jan 1, 2011•0 citations

Wavelength-scale imaging of trapped ions using a phase Fresnel lens

Andreas Jechow, Erik W. Streed, B. G. Norton +2 more

A microfabricated phase Fresnel lens was used to image ytterbium ions trapped in a radio frequency Paul trap. The ions were laser cooled close to the Doppler limit on the 369.5 nm transition, reducing the ion motion so that each ion formed a near point source. By detecting the ion fluorescence on the same transition, near-diffraction-limited imaging with spot sizes of below 440 nm (FWHM) was achieved. To our knowledge, this is the first demonstration of wavelength-scale imaging of trapped ions and the highest imaging resolution ever achieved with atoms in free space.

arXiv:1101.4443•Optics Letters•Apr 7, 2011•38 citations

Spectroscopy of Single Trapped Ions and Application to Frequency Standards

HERBERT WALTHER

Single ions trapped and laser cooled provide ideal objects for high resolution spectroscopy and frequency standards. For the latter purpose we are investigating the 5s2 1S0 → 5s5p 3P0 transition of In+. With a natural linewidth of only 1.1 Hz this resonance offers very high resolution and is highly immune to frequency shifts due to external electromagnetic fields, because it connects two levels with vanishing electronic magnetic momenta [1]. The wavelength of this clock transition is 236.5 nm and is technically very convenient, since it coincides with the fourth harmonic of the 946 nm Nd:YAG laser line. So this intrinsically frequency stable solid-state laser can be used to excite the transition [2]. For laser cooling and fluorescence detection of the indium ion the 5s2 1So -> 5s5p 3P1 transition at 230.6 nm can be employed. The use of the relatively narrow intercombination line for laser cooling allows us to study optical sideband cooling in the strong binding regime, where the oscillation frequencies of the ion in the trap (around 1 MHz) are larger than the optical linewidth of 360 kHz. In this parameter range laser cooling is possible to the quantum ground state of the vibrational motion in the trap corresponding to a temperature of roughly 100 μK. The same low temperature was obtained with sideband cooling of a small Coulomb crystal consisting of two ions, creating an interesting new quantum few-particle system.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jan 1, 1998•0 citations

High-resolution trapped-ion fluorescence imaging via an integrated metalens

Pengcheng Zheng, Zerui Huang, Junxia Li +3 more

We demonstrate the first integration of a metalens inside the ultra-high-vacuum (UHV) chamber of an ion trap, enabling near-diffraction-limited imaging of trapped ions. A single trapped Yb + ion is laser-cooled close to the Lamb–Dicke regime to characterize the metalens performance, achieving a full-width at half-maximum (FWHM) of 1.16 ± 0.09 μm, which aligns closely with the Abbe diffraction limit of 1.15 μm and outperforms conventional external-cavity lenses (2.37 ± 0.12 μm) with the same numerical aperture. We further demonstrate near-diffraction-limited imaging of multi-ion systems over the accessible off-axis range. Our results establish the metalens as a superior optical element for ion fluorescence imaging, providing higher resolution for applications in ion position calibration, multi-qubit readout, and precision measurement. Furthermore, this miniaturized and integrable approach overcomes traditional optical constraints, delivering near-diffraction-limited imaging and advancing the development of compact ion trap platforms.

Optics Letters•Sep 14, 2026•0 citations

Millikelvin spatial thermometry of trapped ions

B. G. Norton, Erik W. Streed, M J Petrasiunas +2 more

We demonstrate millikelvin thermometry of laser-cooled trapped ions with high-resolution imaging. This equilibrium approach is independent of the cooling dynamics and has lower systematic error than Doppler thermometry, with ±5 mK accuracy and ±1 mK precision. We used it to observe the highly anisotropic dynamics of a single ion, finding temperatures of <60 mK and >15 K simultaneously along different directions. This thermometry technique can offer new insights into quantum systems sympathetically cooled by ions, including atoms, molecules, nanomechanical oscillators and electric circuits.

arXiv:1106.1708•New Journal of Physics•Nov 17, 2011•19 citations

Laser cooling and sympathetic cooling in a linear quadrupole rf trap

Vladimir L. Ryjkov

An investigation of the sympathetic cooling \nmethod for the studies of large ultra-cold molecular ions in a quadrupole ion trap has been conducted.Molecular dynamics simulations are performed to study the rf heating mechanisms in the ion trap. The dependence of \nrf heating rates on the ion temperature, trapping parameters, \nand the number of ions is obtained. New rf heating mechanism \naffecting ultra-cold ion clouds exposed to laser radiation is described.The saturation spectroscopy setup of the hyperfine spectra \nof the molecular iodine has been built to provide an accurate frequency reference for the laser wavelength. This reference is used to obtain the fluorescence lineshapes of \nthe laser cooled Mg$^+$ ions under different trapping conditions.The ion temperatures are deduced from the measurements, and \nthe influence of the rf heating rates on the fluorescence lineshapes \nis also discussed. Cooling of the heavy ($m=720$a.u.) fullerene ions to under 10K by the means of the sympathetic cooling by the Mg$^+$ ions($m=24$a.u.) is demonstrated. The single-photon imaging system has been developed and used to obtain the images of the Mg$^+$ ion crystal structures at mK temperatures.

•Feb 17, 2005•0 citations
We have realized wavelength scale fluorescence imaging of trapped Yb+ ions on the 370 nm laser cooling transition. We present results for thermometry of laser cooled trapped ions at temperatures on the order of 100 milli-Kelvin with temperature sensitivities on the order of lOmilli-Kelvin. This technique overcomes the sensitivity limitations of fluorescence spectroscopy in this regime.
A microfabricated phase Fresnel lens was used to image ytterbium ions trapped in a radio frequency Paul trap. The ions were laser cooled close to the Doppler limit on the 369.5 nm transition, reducing the ion motion so that each ion formed a near point source. By detecting the ion fluorescence on the same transition, near-diffraction-limited imaging with spot sizes of below 440 nm (FWHM) was achieved. To our knowledge, this is the first demonstration of wavelength-scale imaging of trapped ions and the highest imaging resolution ever achieved with atoms in free space.
Single ions trapped and laser cooled provide ideal objects for high resolution spectroscopy and frequency standards. For the latter purpose we are investigating the 5s2 1S0 → 5s5p 3P0 transition of In+. With a natural linewidth of only 1.1 Hz this resonance offers very high resolution and is highly immune to frequency shifts due to external electromagnetic fields, because it connects two levels with vanishing electronic magnetic momenta [1]. The wavelength of this clock transition is 236.5 nm and is technically very convenient, since it coincides with the fourth harmonic of the 946 nm Nd:YAG laser line. So this intrinsically frequency stable solid-state laser can be used to excite the transition [2]. For laser cooling and fluorescence detection of the indium ion the 5s2 1So -> 5s5p 3P1 transition at 230.6 nm can be employed. The use of the relatively narrow intercombination line for laser cooling allows us to study optical sideband cooling in the strong binding regime, where the oscillation frequencies of the ion in the trap (around 1 MHz) are larger than the optical linewidth of 360 kHz. In this parameter range laser cooling is possible to the quantum ground state of the vibrational motion in the trap corresponding to a temperature of roughly 100 μK. The same low temperature was obtained with sideband cooling of a small Coulomb crystal consisting of two ions, creating an interesting new quantum few-particle system.
We demonstrate the first integration of a metalens inside the ultra-high-vacuum (UHV) chamber of an ion trap, enabling near-diffraction-limited imaging of trapped ions. A single trapped Yb + ion is laser-cooled close to the Lamb–Dicke regime to characterize the metalens performance, achieving a full-width at half-maximum (FWHM) of 1.16 ± 0.09 μm, which aligns closely with the Abbe diffraction limit of 1.15 μm and outperforms conventional external-cavity lenses (2.37 ± 0.12 μm) with the same numerical aperture. We further demonstrate near-diffraction-limited imaging of multi-ion systems over the accessible off-axis range. Our results establish the metalens as a superior optical element for ion fluorescence imaging, providing higher resolution for applications in ion position calibration, multi-qubit readout, and precision measurement. Furthermore, this miniaturized and integrable approach overcomes traditional optical constraints, delivering near-diffraction-limited imaging and advancing the development of compact ion trap platforms.
We demonstrate millikelvin thermometry of laser-cooled trapped ions with high-resolution imaging. This equilibrium approach is independent of the cooling dynamics and has lower systematic error than Doppler thermometry, with ±5 mK accuracy and ±1 mK precision. We used it to observe the highly anisotropic dynamics of a single ion, finding temperatures of <60 mK and >15 K simultaneously along different directions. This thermometry technique can offer new insights into quantum systems sympathetically cooled by ions, including atoms, molecules, nanomechanical oscillators and electric circuits.
An investigation of the sympathetic cooling \nmethod for the studies of large ultra-cold molecular ions in a quadrupole ion trap has been conducted.Molecular dynamics simulations are performed to study the rf heating mechanisms in the ion trap. The dependence of \nrf heating rates on the ion temperature, trapping parameters, \nand the number of ions is obtained. New rf heating mechanism \naffecting ultra-cold ion clouds exposed to laser radiation is described.The saturation spectroscopy setup of the hyperfine spectra \nof the molecular iodine has been built to provide an accurate frequency reference for the laser wavelength. This reference is used to obtain the fluorescence lineshapes of \nthe laser cooled Mg+^++ ions under different trapping conditions.The ion temperatures are deduced from the measurements, and \nthe influence of the rf heating rates on the fluorescence lineshapes \nis also discussed. Cooling of the heavy (m=720m=720m=720a.u.) fullerene ions to under 10K by the means of the sympathetic cooling by the Mg+^++ ions(m=24m=24m=24a.u.) is demonstrated. The single-photon imaging system has been developed and used to obtain the images of the Mg+^++ ion crystal structures at mK temperatures.