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:1509.05450 · Physical Review A

Imaging electric fields in the vicinity of cryogenic surfaces using Rydberg atoms

T. Thiele, Johannes Deiglmayr, M. Stammeier, Josef A. Agner, Hansjürg Schmutz, Frédéric Merkt, Andreas J. Wallraff

Published Dec 28, 2015• 41 citations
arXivHTMLPDF

Abstract

The ability to characterize static and time-dependent electric fields in situ is an important prerequisite for quantum-optics experiments with atoms close to surfaces. Especially in experiments which aim at coupling Rydberg atoms to the near field of superconducting circuits, the identification and subsequent elimination of sources of stray fields are crucial. We present a technique that allows the determination of stray-electric-field distributions $[{F}_{\mathrm{x}}^{\mathrm{str}}(\stackrel{P\vec}{r}),{F}_{\mathrm{y}}^{\mathrm{str}}(\stackrel{P\vec}{r}),{F}_{\mathrm{z}}^{\mathrm{str}}(\stackrel{P\vec}{r})]$ at distances of less than 2 mm from (cryogenic) surfaces using coherent Rydberg-Stark spectroscopy in a pulsed supersonic beam of metastable $1{s}^{1}2{s}^{1}{}^{1}{S}_{0}$ helium atoms. We demonstrate the capabilities of this technique by characterizing the electric stray field emanating from a structured superconducting surface. Exploiting coherent population transfer with microwave radiation from a coplanar waveguide, the same technique allows the characterization of the microwave-field distribution above the surface.

DOI
10.1103/physreva.92.063425

Related papers

Manipulating Rydberg atoms close to surfaces at cryogenic temperatures

T. Thiele, Stefan Filipp, Josef A. Agner +6 more

Helium atoms in Rydberg states have been manipulated coherently with microwave radiation pulses near a gold surface and near a superconducting NbTiN surface at a temperature of $3\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. The experiments were carried out with a skimmed supersonic beam of metastable ${(1s)}^{1}{(2s)}^{1}\phantom{\rule{0.28em}{0ex}}{}^{1}{S}_{0}$ helium atoms excited with laser radiation to $np$ Rydberg levels with principal quantum number $n$ between 30 and 40. The separation between the cold surface and the center of the collimated beam is adjustable down to $250\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$. Short-lived $np$ Rydberg states were coherently transferred to the long-lived $ns$ state to avoid radiative decay of the Rydberg atoms between the photoexcitation region and the region above the cold surfaces. Further coherent manipulation of the $ns$ Rydberg states with pulsed microwave radiation above the surfaces enabled measurements of stray electric fields and allowed us to study the decoherence of the atomic ensemble. Adsorption of residual gas onto the surfaces and the resulting slow buildup of stray fields was minimized by controlling the temperature of the surface and monitoring the partial pressures of ${\mathrm{H}}_{2}\mathrm{O}$, ${\mathrm{N}}_{2}$, ${\mathrm{O}}_{2}$, and $\mathrm{C}{\mathrm{O}}_{2}$ in the experimental chamber during the cool-down procedure. Compensation of the stray electric fields to levels below $100\phantom{\rule{0.28em}{0ex}}\mathrm{mV}/\mathrm{cm}$ was achieved over a region of $6\phantom{\rule{0.28em}{0ex}}\mathrm{mm}$ along the beam-propagation direction which, for the $1770\text{-m}/\mathrm{s}$ beam velocity, implies the possibility to preserve the coherence of the atomic sample for several microseconds above the cold surfaces.

arXiv:1402.7217•Physical Review A•Jul 14, 2014•41 citations

Driving Rydberg-Rydberg Transitions from a Coplanar Microwave Waveguide

S. D. Hogan, Josef A. Agner, Frédéric Merkt +3 more

The coherent interaction between ensembles of helium Rydberg atoms and microwave fields in the vicinity of a solid-state coplanar waveguide is reported. Rydberg-Rydberg transitions, at frequencies between 25 and 38 GHz, have been studied for states with principal quantum numbers in the range 30-35 by selective electric-field ionization. An experimental apparatus cooled to 100 K was used to reduce effects of blackbody radiation. Inhomogeneous, stray electric fields emanating from the surface of the waveguide have been characterized in frequency- and time-resolved measurements and coherence times of the Rydberg atoms on the order of 250 ns have been determined. These results represent a key element in the development of an experimental architecture to interface Rydberg atoms with solid-state devices.

arXiv:1110.1256•Physical Review Letters•Feb 9, 2012•111 citations

Coupling Rydberg Atoms to Microwave Fields in a Superconducting Coplanar Waveguide Resonator

A. A. Morgan, S. D. Hogan

Rydberg helium atoms traveling in pulsed supersonic beams have been coupled to microwave fields in a superconducting coplanar waveguide (CPW) resonator. The atoms were initially prepared in the 1s55s ^{3}S_{1} Rydberg level by two-color two-photon laser excitation from the metastable 1s2s ^{3}S_{1} level. Two-photon microwave transitions between the 1s55s ^{3}S_{1} and 1s56s ^{3}S_{1} levels were then driven by the 19.556 GHz third-harmonic microwave field in a quarter-wave CPW resonator. This superconducting microwave resonator was fabricated from niobium nitride on a silicon substrate and operated at temperatures between 3.65 and 4.30 K. The populations of the Rydberg levels in the experiments were determined by state-selective pulsed electric field ionization. The coherence of the atom-resonator coupling was studied by time-domain measurements of Rabi oscillations.

arXiv:1911.05513•Physical Review Letters•May 12, 2020•45 citations

Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

D. Davtyan, Shimon Machluf, Maarten L. Soudijn +4 more

Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than $0.2\phantom{\rule{0.28em}{0ex}}\mathrm{V}/\mathrm{cm}$ at $78\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

arXiv:1710.05301•Physical Review A•Feb 22, 2018•12 citations

Demonstration of a tunable interface between Rydberg atoms and superconducting microwave circuits with differential polarizability nulling

L. L. Brown, J. A. L. Grondin, S. D. Hogan

Microwave-dressed Rydberg atoms in pairs of states that are optically accessible and engineered so that the frequency of the transition between them is tunable while exhibiting a low sensitivity to stray electric fields have been interfaced with a superconducting coplanar waveguide (CPW) microwave resonator. This was achieved with helium atoms in triplet Rydberg states with principal quantum numbers n = 55 and 56. The atoms were dressed with two strong microwave fields—a control field and a differential polarizability nulling field. The control field allowed the atoms to be coupled to the resonator using the two-color two-photon transition between the equal parity 1 s 55 s S 1 3 ≡ | 55 s 〉 and 1 s 56 s S 1 3 ≡ | 56 s 〉 Rydberg states, with one photon supplied by it and the other provided by the resonator. The nulling field was detuned from the field-free 1 s 55 s S 1 3 → 1 s 55 p P J 3 ≡ | 55 p 〉 transition to admix | 55 p 〉 character into the | 55 s 〉 state and eliminate the differential static electric dipole polarizability of the | 55 s 〉 and | 56 s 〉 states. The experiments were performed with atoms located ∼ 300 µ m above a λ / 4 niobium nitride superconducting CPW resonator operated at temperatures between 3.59 and 3.73 K . The measured ac and dc Stark shifts of the Rydberg states at this atom-circuit interface in the presence of the dressing fields are in good quantitative agreement with the results of Floquet calculations. The differential polarizability nulling fields used in the experiments allowed the difference in the Stark shifts of the | 55 s 〉 and | 56 s 〉 states over the range of dc fields offset from the residual stray field by ± 65 mV/cm to be reduced from 2 π × 2.1 MHz to 2 π × 125 kHz. Published by the American Physical Society 2024

Physical Review A•Aug 19, 2024•4 citations

Electrometry of a single resonator mode at a Rydberg-atom–superconducting-circuit interface

D. M. Walker, L. L. Brown, S. D. Hogan

The electric-field distribution in a single mode of a $\ensuremath{\lambda}/4$ superconducting coplanar waveguide (CPW) microwave resonator has been probed using beams of helium Rydberg atoms. In the experiments the atoms were prepared in the $1\mathrm{s}55\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}$ Rydberg level by laser photoexcitation. They then traveled over the CPW resonator that was fabricated on a NbN superconducting chip operated at 3.8 K. The resonator was driven at its third-harmonic frequency, near resonant with the two-photon $1\mathrm{s}55\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}\ensuremath{\rightarrow}1\mathrm{s}56\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}$ transition at ${\ensuremath{\omega}}_{55\mathrm{s},\phantom{\rule{0.16em}{0ex}}56\mathrm{s}}/2=2\ensuremath{\pi}\phantom{\rule{0.16em}{0ex}}\ifmmode\times\else\texttimes\fi{}\phantom{\rule{0.16em}{0ex}}19.556\phantom{\rule{0.16em}{0ex}}499$ GHz. The coherence times of the atom--resonator-field interaction were determined at selected locations above the resonator by time-domain measurements of Rabi oscillations and found to be up to $0.8\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{s}$ for Rabi frequencies of $\ensuremath{\sim}2\ensuremath{\pi}\phantom{\rule{0.16em}{0ex}}\ifmmode\times\else\texttimes\fi{}\phantom{\rule{0.16em}{0ex}}3$ MHz. The coherence times of the atomic superposition states, generated following the interaction of the atoms with the microwave field in the resonator, were inferred from high-resolution cavity-enhanced Ramsey spectra to be $\ensuremath{\sim}2.5\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{s}$. These Ramsey spectra also allowed the measurement of residual uncanceled dc electric fields of $26.6\ifmmode\pm\else\textpm\fi{}0.6$ mV/cm at the position of the atoms $\ensuremath{\sim}300\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{m}$ above the surface of the superconducting chip. These results represent an essential step toward applications of hybrid systems, comprising Rydberg atoms coherently coupled to superconducting microwave circuits, in quantum optics and quantum information processing.

Physical Review A•Feb 28, 2022•8 citations
The ability to characterize static and time-dependent electric fields in situ is an important prerequisite for quantum-optics experiments with atoms close to surfaces. Especially in experiments which aim at coupling Rydberg atoms to the near field of superconducting circuits, the identification and subsequent elimination of sources of stray fields are crucial. We present a technique that allows the determination of stray-electric-field distributions [{F}_{\mathrm{x}}^{\mathrm{str}}(\stackrel{P\vec}{r}),{F}_{\mathrm{y}}^{\mathrm{str}}(\stackrel{P\vec}{r}),{F}_{\mathrm{z}}^{\mathrm{str}}(\stackrel{P\vec}{r})] at distances of less than 2 mm from (cryogenic) surfaces using coherent Rydberg-Stark spectroscopy in a pulsed supersonic beam of metastable 1s12s11S01{s}^{1}2{s}^{1}{}^{1}{S}_{0}1s12s11S0​ helium atoms. We demonstrate the capabilities of this technique by characterizing the electric stray field emanating from a structured superconducting surface. Exploiting coherent population transfer with microwave radiation from a coplanar waveguide, the same technique allows the characterization of the microwave-field distribution above the surface.
Helium atoms in Rydberg states have been manipulated coherently with microwave radiation pulses near a gold surface and near a superconducting NbTiN surface at a temperature of 3K3\phantom{\rule{0.28em}{0ex}}\mathrm{K}3K. The experiments were carried out with a skimmed supersonic beam of metastable (1s)1(2s)11S0{(1s)}^{1}{(2s)}^{1}\phantom{\rule{0.28em}{0ex}}{}^{1}{S}_{0}(1s)1(2s)11S0​ helium atoms excited with laser radiation to npnpnp Rydberg levels with principal quantum number nnn between 30 and 40. The separation between the cold surface and the center of the collimated beam is adjustable down to $250\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$. Short-lived npnpnp Rydberg states were coherently transferred to the long-lived nsnsns state to avoid radiative decay of the Rydberg atoms between the photoexcitation region and the region above the cold surfaces. Further coherent manipulation of the nsnsns Rydberg states with pulsed microwave radiation above the surfaces enabled measurements of stray electric fields and allowed us to study the decoherence of the atomic ensemble. Adsorption of residual gas onto the surfaces and the resulting slow buildup of stray fields was minimized by controlling the temperature of the surface and monitoring the partial pressures of H2O{\mathrm{H}}_{2}\mathrm{O}H2​O, N2{\mathrm{N}}_{2}N2​, O2{\mathrm{O}}_{2}O2​, and CO2\mathrm{C}{\mathrm{O}}_{2}CO2​ in the experimental chamber during the cool-down procedure. Compensation of the stray electric fields to levels below 100mV/cm100\phantom{\rule{0.28em}{0ex}}\mathrm{mV}/\mathrm{cm}100mV/cm was achieved over a region of 6mm6\phantom{\rule{0.28em}{0ex}}\mathrm{mm}6mm along the beam-propagation direction which, for the 1770-m/s1770\text{-m}/\mathrm{s}1770-m/s beam velocity, implies the possibility to preserve the coherence of the atomic sample for several microseconds above the cold surfaces.
The coherent interaction between ensembles of helium Rydberg atoms and microwave fields in the vicinity of a solid-state coplanar waveguide is reported. Rydberg-Rydberg transitions, at frequencies between 25 and 38 GHz, have been studied for states with principal quantum numbers in the range 30-35 by selective electric-field ionization. An experimental apparatus cooled to 100 K was used to reduce effects of blackbody radiation. Inhomogeneous, stray electric fields emanating from the surface of the waveguide have been characterized in frequency- and time-resolved measurements and coherence times of the Rydberg atoms on the order of 250 ns have been determined. These results represent a key element in the development of an experimental architecture to interface Rydberg atoms with solid-state devices.
Rydberg helium atoms traveling in pulsed supersonic beams have been coupled to microwave fields in a superconducting coplanar waveguide (CPW) resonator. The atoms were initially prepared in the 1s55s ^{3}S_{1} Rydberg level by two-color two-photon laser excitation from the metastable 1s2s ^{3}S_{1} level. Two-photon microwave transitions between the 1s55s ^{3}S_{1} and 1s56s ^{3}S_{1} levels were then driven by the 19.556 GHz third-harmonic microwave field in a quarter-wave CPW resonator. This superconducting microwave resonator was fabricated from niobium nitride on a silicon substrate and operated at temperatures between 3.65 and 4.30 K. The populations of the Rydberg levels in the experiments were determined by state-selective pulsed electric field ionization. The coherence of the atom-resonator coupling was studied by time-domain measurements of Rabi oscillations.
Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2V/cm0.2\phantom{\rule{0.28em}{0ex}}\mathrm{V}/\mathrm{cm}0.2V/cm at $78\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.
Microwave-dressed Rydberg atoms in pairs of states that are optically accessible and engineered so that the frequency of the transition between them is tunable while exhibiting a low sensitivity to stray electric fields have been interfaced with a superconducting coplanar waveguide (CPW) microwave resonator. This was achieved with helium atoms in triplet Rydberg states with principal quantum numbers n = 55 and 56. The atoms were dressed with two strong microwave fields—a control field and a differential polarizability nulling field. The control field allowed the atoms to be coupled to the resonator using the two-color two-photon transition between the equal parity 1 s 55 s S 1 3 ≡ | 55 s 〉 and 1 s 56 s S 1 3 ≡ | 56 s 〉 Rydberg states, with one photon supplied by it and the other provided by the resonator. The nulling field was detuned from the field-free 1 s 55 s S 1 3 → 1 s 55 p P J 3 ≡ | 55 p 〉 transition to admix | 55 p 〉 character into the | 55 s 〉 state and eliminate the differential static electric dipole polarizability of the | 55 s 〉 and | 56 s 〉 states. The experiments were performed with atoms located ∼ 300 µ m above a λ / 4 niobium nitride superconducting CPW resonator operated at temperatures between 3.59 and 3.73 K . The measured ac and dc Stark shifts of the Rydberg states at this atom-circuit interface in the presence of the dressing fields are in good quantitative agreement with the results of Floquet calculations. The differential polarizability nulling fields used in the experiments allowed the difference in the Stark shifts of the | 55 s 〉 and | 56 s 〉 states over the range of dc fields offset from the residual stray field by ± 65 mV/cm to be reduced from 2 π × 2.1 MHz to 2 π × 125 kHz. Published by the American Physical Society 2024
The electric-field distribution in a single mode of a $\ensuremath{\lambda}/4$ superconducting coplanar waveguide (CPW) microwave resonator has been probed using beams of helium Rydberg atoms. In the experiments the atoms were prepared in the 1s55s3S11\mathrm{s}55\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}1s55s3S1​ Rydberg level by laser photoexcitation. They then traveled over the CPW resonator that was fabricated on a NbN superconducting chip operated at 3.8 K. The resonator was driven at its third-harmonic frequency, near resonant with the two-photon $1\mathrm{s}55\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}\ensuremath{\rightarrow}1\mathrm{s}56\mathrm{s}{\phantom{\rule{0.16em}{0ex}}}^{3}{\mathrm{S}}_{1}$ transition at ${\ensuremath{\omega}}_{55\mathrm{s},\phantom{\rule{0.16em}{0ex}}56\mathrm{s}}/2=2\ensuremath{\pi}\phantom{\rule{0.16em}{0ex}}\ifmmode\times\else\texttimes\fi{}\phantom{\rule{0.16em}{0ex}}19.556\phantom{\rule{0.16em}{0ex}}499$ GHz. The coherence times of the atom--resonator-field interaction were determined at selected locations above the resonator by time-domain measurements of Rabi oscillations and found to be up to $0.8\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{s}$ for Rabi frequencies of $\ensuremath{\sim}2\ensuremath{\pi}\phantom{\rule{0.16em}{0ex}}\ifmmode\times\else\texttimes\fi{}\phantom{\rule{0.16em}{0ex}}3$ MHz. The coherence times of the atomic superposition states, generated following the interaction of the atoms with the microwave field in the resonator, were inferred from high-resolution cavity-enhanced Ramsey spectra to be $\ensuremath{\sim}2.5\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{s}$. These Ramsey spectra also allowed the measurement of residual uncanceled dc electric fields of $26.6\ifmmode\pm\else\textpm\fi{}0.6$ mV/cm at the position of the atoms $\ensuremath{\sim}300\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{m}$ above the surface of the superconducting chip. These results represent an essential step toward applications of hybrid systems, comprising Rydberg atoms coherently coupled to superconducting microwave circuits, in quantum optics and quantum information processing.