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

Optica Quantum

Enabling atom-clad waveguide operation in a microfabricated alkali vapor–photonic integrated circuit

Rahul Shrestha, Khoi Tuan Hoang, Peter Riley, Roy Zektzer, Daron Westly, Paul D. Lett, Matthew T. Hummon, Kartik A. Srinivasan

Published Mar 17, 2026• 3 citations
Publisher

Abstract

Integrating alkali atomic vapors with nanophotonic devices offers a scalable route to quantum technologies that leverage strong atom–photon interactions. While there have been many approaches to such integration, the general reliance on traditional glass vapor cells, distilled alkali metals, and epoxy sealing limits reproducibility and scalability. Moreover, mitigating adverse Rb-photonics interactions is essential, particularly as devices become more compact and the alkali source lies in close proximity to the photonic elements. Here, we demonstrate the successful operation of compact and fully integrated devices that combine silicon nitride photonic integrated circuits (PICs) with microfabricated borosilicate vapor cells and pill-type rubidium (Rb) dispensers through hermetic seals via anodic bonding. We show how successful operation hinges on optically activating the dispenser in a low-power pulsed mode, releasing controlled amounts of Rb vapor on demand while mitigating photonic degradation. Simultaneously, a counter-propagating desorption laser completely suppresses Rb-induced losses and enables waveguide-based atomic vapor spectroscopy. Using this approach, we demonstrate repeatable control of vapor density by tuning activation pulse length, duty cycle, and device temperature. These results establish a compact, manufacturable, and scalable vapor–PIC device, and set the stage for future demonstrations in cavity quantum electrodynamics, quantum nonlinear optics, and chip-scale atomic sensors.

DOI
10.1364/opticaq.587669

Related papers

Enabling atom-clad waveguide operation in a microfabricated alkali vapor-photonic integrated circuit

Rahul Shrestha, Khoi Tuan Hoang, Peter Riley +5 more

Integrating alkali atomic vapors with nanophotonic devices offers a scalable route to quantum technologies that leverage strong atom-photon interactions. While there have been many approaches to such integration, the general reliance on traditional glass vapor cells, distilled alkali metals, and epoxy sealing limits reproducibility and scalability. Moreover, mitigating adverse Rb-photonics interactions is essential, particularly as devices become more compact and the alkali source lies in close proximity to the photonic elements. Here, we demonstrate the successful operation of compact and fully integrated devices that combine silicon nitride photonic integrated circuits (PICs) with microfabricated borosilicate vapor cells and pill-type rubidium (Rb) dispensers through hermetic seals via anodic bonding. We show how successful operation hinges on optically activating the dispenser in a low-power pulsed mode, releasing controlled amounts of Rb vapor on demand while mitigating photonic degradation. Simultaneously, a counter-propagating desorption laser completely suppresses Rb-induced losses and enables waveguide-based atomic vapor spectroscopy. Using this approach, we demonstrate repeatable control of vapor density by tuning activation pulse length, duty cycle, and device temperature. These results establish a compact, manufacturable, and scalable vapor-PIC device, and set the stage for future demonstrations in cavity quantum electrodynamics, quantum nonlinear optics, and chip-scale atomic sensors.

arXiv:2512.19852•Dec 22, 2025•0 citations

Cavity QED in a fully integrated atomic-photonic vapor cell with a pulsed alkali source

Rahul Shrestha, Khoi Tuan Hoang, Peter Riley +5 more

We demonstrate a fully integrated platform for experiments with warm Rb atoms and chip-integrated high-Q (≈ 105) photonic microcavities. Pulsed activation of an alkali dispenser pill enables temperature-independent control of Rb density and resulting cavity interactions.

•Jan 1, 2025•0 citations

Wafer‐scale integration of photonic integrated circuits and atomic vapor cells

Arieh Grosman, Roy Zektzer, Noa Mazurski +2 more

Atom-based technologies have played a central role in both fundamental research and application-driven developments. For example, devices such as atomic clocks and magnetometers are essential for precision time-keeping, navigation, and sensing. However, many of these demonstrations remain confined to laboratory settings due to their reliance on bulky equipment and centimeter-scale atomic vapor cells. In recent years, significant efforts have been made to miniaturize these vapor cells to enable field-deployable systems. Yet, integrating these cells with the necessary photonic components remains a complex and non-scalable process. To address this challenge, we have introduced the atomic-cladded waveguide (ACWG) architecture, which enables the integration of atomic and photonic functions on the same chip. While the ACWG concept provides a significant step forward toward integration, there is still a significant gap related to wafer scale manufacturability. In particular, previous demonstrations of atomic-photonic integration have relied on manual assembly of vapor cells onto single chips, restricting miniaturization, manufacturability, and thermal robustness. To revolutionize manufacturability of these devices, we hereby demonstrate our new generation of ACWG devices that overcomes these constraints. The approach is based on wafer bonding of a silicon wafer - consisting of multiple photonic chips to a glass wafer with pre-etched atomic chambers. This wafer-scale process yields multiple miniaturized integrated photonic-atomic chips in a single batch. The bonded devices operate reliably at elevated temperatures over an extended period of time, allowing higher atomic densities to be used. The fabrication method consists of well-defined, repeatable steps, paving the way for scalable production of mature integrated photonic-atomic systems for next-generation sensing, metrology, and quantum technologies, inspired by commercial complementary metal-oxide-semiconductor-based processes.

Nanophotonics•Dec 1, 2025•7 citations

Demonstration of atom interrogation using photonic integrated circuits anodically bonded to ultra-high vacuum envelopes for epoxy-free scalable quantum sensors

Sterling E. McBride, Cale M. Gentry, Christopher E. Holland +3 more

Reliable integration of photonic integrated circuits (PICs) into quantum sensors has the potential to drastically reduce sensor size, ease manufacturing scalability, and improve performance in applications where the sensor is subject to high accelerations, vibrations, and temperature changes. In a traditional quantum sensor assembly, free-space optics are subject to pointing inaccuracies and temperature-dependent misalignment. Moreover, the use of epoxy or sealants for affixing either free-space optics or PICs within a sensor vacuum envelope leads to sensor vacuum degradation and is difficult to scale. In this paper, we describe the hermetic integration of a PIC with a vacuum envelope via anodic bonding. We demonstrate utility of this assembly with two proof-of-concept atom-interrogation experiments: (i) spectroscopy of a cold-atom sample using a grating-emitted probe; (ii) spectroscopy of alkali atoms using an evanescent field from an exposed ridge waveguide. This work shows a key process step on a path to quantum sensor manufacturing scalability.

arXiv:2409.05254•Optica Quantum•Dec 23, 2024•2 citations

Evanescent Light-Matter Interaction in an Integrated MEMS – Nanophotonic Vapor Cell

Peter Riley, Khoi Tuan Hoang, Rahul Shrestha +4 more

We demonstrate a microfabricated atomic vapor cell directly bonded to a silicon nitride photonic chip. The integrated device enables robust operation and evanescent-field spectroscopy of Rb vapor at operating temperatures as high as 300 °C.

•Jan 1, 2025•0 citations

Sealing techniques for on-chip atomic vapor cells

John F. Hulbert, Brandon T. Carroll, Aaron R. Hawkins +2 more

We have recently reported atomic spectroscopy using on-chip rubidium vapor cells based on hollow core waveguides. To make the cells more robust and capable of multiple temperature cycles, we examined several techniques for Rb introduction and sealing. To date the most successful sealing technique has been pinching off the end of a short length of copper tubing. This technique not only hermetically seals the cells, but also allows them to be evacuated to a desired pressure. We have been able to evacuate glass prototype Rb vapor cells to a pressure as low as 80 mTorr and as high as 2 Torr and successfully observe the Rb optical absorption spectrum. Along with our testing of sealing techniques we have been observing the effects of different epoxies and inert gas atmospheres on the robustness of vapor cells. With optimal parameters we have successfully observed the Rb optical absorption spectrum through multiple temperature cycles. These new Rb introduction and sealing methods will be applied to on-chip cells containing integrated hollow waveguides which can be used for a number of different optical applications, such as electromagnetically induced transparency, single-photon nonlinearities, and slow light.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jan 10, 2008•1 citation
Integrating alkali atomic vapors with nanophotonic devices offers a scalable route to quantum technologies that leverage strong atom–photon interactions. While there have been many approaches to such integration, the general reliance on traditional glass vapor cells, distilled alkali metals, and epoxy sealing limits reproducibility and scalability. Moreover, mitigating adverse Rb-photonics interactions is essential, particularly as devices become more compact and the alkali source lies in close proximity to the photonic elements. Here, we demonstrate the successful operation of compact and fully integrated devices that combine silicon nitride photonic integrated circuits (PICs) with microfabricated borosilicate vapor cells and pill-type rubidium (Rb) dispensers through hermetic seals via anodic bonding. We show how successful operation hinges on optically activating the dispenser in a low-power pulsed mode, releasing controlled amounts of Rb vapor on demand while mitigating photonic degradation. Simultaneously, a counter-propagating desorption laser completely suppresses Rb-induced losses and enables waveguide-based atomic vapor spectroscopy. Using this approach, we demonstrate repeatable control of vapor density by tuning activation pulse length, duty cycle, and device temperature. These results establish a compact, manufacturable, and scalable vapor–PIC device, and set the stage for future demonstrations in cavity quantum electrodynamics, quantum nonlinear optics, and chip-scale atomic sensors.
Integrating alkali atomic vapors with nanophotonic devices offers a scalable route to quantum technologies that leverage strong atom-photon interactions. While there have been many approaches to such integration, the general reliance on traditional glass vapor cells, distilled alkali metals, and epoxy sealing limits reproducibility and scalability. Moreover, mitigating adverse Rb-photonics interactions is essential, particularly as devices become more compact and the alkali source lies in close proximity to the photonic elements. Here, we demonstrate the successful operation of compact and fully integrated devices that combine silicon nitride photonic integrated circuits (PICs) with microfabricated borosilicate vapor cells and pill-type rubidium (Rb) dispensers through hermetic seals via anodic bonding. We show how successful operation hinges on optically activating the dispenser in a low-power pulsed mode, releasing controlled amounts of Rb vapor on demand while mitigating photonic degradation. Simultaneously, a counter-propagating desorption laser completely suppresses Rb-induced losses and enables waveguide-based atomic vapor spectroscopy. Using this approach, we demonstrate repeatable control of vapor density by tuning activation pulse length, duty cycle, and device temperature. These results establish a compact, manufacturable, and scalable vapor-PIC device, and set the stage for future demonstrations in cavity quantum electrodynamics, quantum nonlinear optics, and chip-scale atomic sensors.
Atom-based technologies have played a central role in both fundamental research and application-driven developments. For example, devices such as atomic clocks and magnetometers are essential for precision time-keeping, navigation, and sensing. However, many of these demonstrations remain confined to laboratory settings due to their reliance on bulky equipment and centimeter-scale atomic vapor cells. In recent years, significant efforts have been made to miniaturize these vapor cells to enable field-deployable systems. Yet, integrating these cells with the necessary photonic components remains a complex and non-scalable process. To address this challenge, we have introduced the atomic-cladded waveguide (ACWG) architecture, which enables the integration of atomic and photonic functions on the same chip. While the ACWG concept provides a significant step forward toward integration, there is still a significant gap related to wafer scale manufacturability. In particular, previous demonstrations of atomic-photonic integration have relied on manual assembly of vapor cells onto single chips, restricting miniaturization, manufacturability, and thermal robustness. To revolutionize manufacturability of these devices, we hereby demonstrate our new generation of ACWG devices that overcomes these constraints. The approach is based on wafer bonding of a silicon wafer - consisting of multiple photonic chips to a glass wafer with pre-etched atomic chambers. This wafer-scale process yields multiple miniaturized integrated photonic-atomic chips in a single batch. The bonded devices operate reliably at elevated temperatures over an extended period of time, allowing higher atomic densities to be used. The fabrication method consists of well-defined, repeatable steps, paving the way for scalable production of mature integrated photonic-atomic systems for next-generation sensing, metrology, and quantum technologies, inspired by commercial complementary metal-oxide-semiconductor-based processes.
Reliable integration of photonic integrated circuits (PICs) into quantum sensors has the potential to drastically reduce sensor size, ease manufacturing scalability, and improve performance in applications where the sensor is subject to high accelerations, vibrations, and temperature changes. In a traditional quantum sensor assembly, free-space optics are subject to pointing inaccuracies and temperature-dependent misalignment. Moreover, the use of epoxy or sealants for affixing either free-space optics or PICs within a sensor vacuum envelope leads to sensor vacuum degradation and is difficult to scale. In this paper, we describe the hermetic integration of a PIC with a vacuum envelope via anodic bonding. We demonstrate utility of this assembly with two proof-of-concept atom-interrogation experiments: (i) spectroscopy of a cold-atom sample using a grating-emitted probe; (ii) spectroscopy of alkali atoms using an evanescent field from an exposed ridge waveguide. This work shows a key process step on a path to quantum sensor manufacturing scalability.
We have recently reported atomic spectroscopy using on-chip rubidium vapor cells based on hollow core waveguides. To make the cells more robust and capable of multiple temperature cycles, we examined several techniques for Rb introduction and sealing. To date the most successful sealing technique has been pinching off the end of a short length of copper tubing. This technique not only hermetically seals the cells, but also allows them to be evacuated to a desired pressure. We have been able to evacuate glass prototype Rb vapor cells to a pressure as low as 80 mTorr and as high as 2 Torr and successfully observe the Rb optical absorption spectrum. Along with our testing of sealing techniques we have been observing the effects of different epoxies and inert gas atmospheres on the robustness of vapor cells. With optimal parameters we have successfully observed the Rb optical absorption spectrum through multiple temperature cycles. These new Rb introduction and sealing methods will be applied to on-chip cells containing integrated hollow waveguides which can be used for a number of different optical applications, such as electromagnetically induced transparency, single-photon nonlinearities, and slow light.