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

OSA Quantum 2.0 Conference

Photon-photon processes in Room-Temperature Rubidium cells using effective χ2 nonlinearities

Steven Sagona-Stophel, Dounan Du, Eden V. Figueroa

Published Jan 1, 2020• 0 citations
Publisher

Abstract

We investigate how a simple room-temperature Rb cell can exhibit both linear and nonlinear quantum processes and achieve a number of benchmarks toward two-photon gate operation, including large photon-photon phase shifts at high-fidelity and optimizing an EIT-enhanced effective χ2 nonlinearity.
DOI
10.1364/quantum.2020.qw6a.14

Related papers

Photon-Photon Quantum Phase Gate in a Photonic Molecule with χ(2) Nonlinearity

Ming Li, Yan-Lei Zhang, Hong X. Tang +3 more

The quantum logic between single photons lies at the foundation of deterministic, scalable quantum information processing. However, practical implementation suffers from weak optical nonlinearity, and gate fidelity is intrinsically limited by phase noise and spectral mixing. The authors address these concerns by utilizing an ultrahigh-$Q$ photonic microcavity with ${\ensuremath{\chi}}^{2}$ nonlinearity. Two-photon spontaneous emission is thoroughly suppressed by shutting off the coupling channels between this artificial atom and the continuum states of a waveguide. This promising scheme for room-temperature operation is almost within reach of current experiments, and can be generalized to other systems.

arXiv:1909.10839•Physical Review Applied•Apr 6, 2020•38 citations

Benchmarking photon-photon interaction nodes for quantum communication

Bertus Jordaan, Mehdi Namazi, Steven Sagona-Stophel +3 more

Summary form only given. Achieving photon-photon interactions is one of the main objectives of the quantum information technology community, since these interactions provide the basis for deterministic quantum gates with high fidelity. In the last few years new milestones in creating phase-shifts [1] and quantum gates[2] have been achieved. Researching resource-moderate experimental realizations for the future development of this field provides a scalable framework for devices and opportunities for deployment in quantum communication networks.We highlight photon-photon interactions in unexplored physical regimes that are outside the standard approach of single atom QED or Rydberg transitions. Building on the first complete quantum optical characterization of an engineered free space phase shift triggered via atomic Kerr nonlinearities [3], we characterize novel architectures using the interaction of single photons in both a room temperature atomic vapor and cold atomic ensembles in miniaturized cavity QED setups. These different systems provide very compelling pathways to achieving photonphoton interactions.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2017•0 citations

A Room Temperature Quantum Memory

Mahdi Hosseini, Geoff Campbell, Ben M. Sparkes +2 more

We present experimental results of high efficiency quantum state storage in a warm rubidium vapour cell using the gradient echo memory (GEM) technique. Without conditional measurements, we show recall fidelity up to 98% for coherent pulses containing around one photon.

•Jan 1, 2011•0 citations

A room temperature quantum memory

Mahdi Hosseini, Geoff Campbell, Ben M. Sparkes +2 more

We present experimental results of high efficiency quantum state storage in a warm rubidium vapour cell using the gradient echo memory (GEM) technique. Without conditional measurements, we show recall fidelity up to 98% for coherent pulses containing around one photon.

•Aug 1, 2011•0 citations

Towards Single Photon Nonlinearities using Cavity EIT

Z. Burkley

In third order nonlinear mediums, the intensity of one optical field can modify the phase of another optical field. This is known as cross-phase modulation (XPM) and is important for Quantum Information Processing (QIP) as phase shifts of single-photons that exceed π rad can be used to implement two-qubit quantum logic gates. For a conventional XPM scheme, the Kerr nonlinearity responsible for XPM is too small for appreciable phase shifts to be achieved with low intensity optical fields. However, Electromagnetically Induced Transparency (EIT) can increase this nonlinearity by several orders of magnitude. This thesis discusses the experimental construction of a laser-atomic system capable of EIT modulated XPM. This includes construction of a rubidium magneto-optical trap (RbMOT), characterization of this RbMOT, demonstration of EIT in the RbMOT, and a system capable of detecting optical phase shifts produced by EIT. The talk will conclude with an outlook on further implementations to the experiment that will increase this nonlinearity such that phase shifts at the single-photon level are possible. | 76 pages

•Jan 1, 2014•0 citations

A Comprehensive Review of Rubidium Two-Photon Vapor Cell Optical Clock: Long-Term Performance Limitations and Potential Improvements

Asagwegbe C. Obaze-Adeleke, Bryan Semon, Thejesh Bandi

Two-photon vapor cell-based optical clocks are strong candidates for next-generation portable atomic standards, offering simplicity, compactness, and high performance. Their narrow clock transitions with counter-propagating beams enable first-order Doppler-free operation. However, systematic perturbations such as the AC Stark shift, temperature-induced shift, and drifts resulting from the laser system pose challenges cause instabilities to medium- to long-term performance. This paper provides a comprehensive overview of Rb two-photon vapor cell optical standards, focusing on the long-term performance-limiting effects and potential mitigation strategies, aiming for clock stabilities better than 1 × 10−15 over the averaging time of a day and beyond.

Photonics•May 20, 2025•10 citations
The quantum logic between single photons lies at the foundation of deterministic, scalable quantum information processing. However, practical implementation suffers from weak optical nonlinearity, and gate fidelity is intrinsically limited by phase noise and spectral mixing. The authors address these concerns by utilizing an ultrahigh-QQQ photonic microcavity with ${\ensuremath{\chi}}^{2}$ nonlinearity. Two-photon spontaneous emission is thoroughly suppressed by shutting off the coupling channels between this artificial atom and the continuum states of a waveguide. This promising scheme for room-temperature operation is almost within reach of current experiments, and can be generalized to other systems.
Summary form only given. Achieving photon-photon interactions is one of the main objectives of the quantum information technology community, since these interactions provide the basis for deterministic quantum gates with high fidelity. In the last few years new milestones in creating phase-shifts [1] and quantum gates[2] have been achieved. Researching resource-moderate experimental realizations for the future development of this field provides a scalable framework for devices and opportunities for deployment in quantum communication networks.We highlight photon-photon interactions in unexplored physical regimes that are outside the standard approach of single atom QED or Rydberg transitions. Building on the first complete quantum optical characterization of an engineered free space phase shift triggered via atomic Kerr nonlinearities [3], we characterize novel architectures using the interaction of single photons in both a room temperature atomic vapor and cold atomic ensembles in miniaturized cavity QED setups. These different systems provide very compelling pathways to achieving photonphoton interactions.
In third order nonlinear mediums, the intensity of one optical field can modify the phase of another optical field. This is known as cross-phase modulation (XPM) and is important for Quantum Information Processing (QIP) as phase shifts of single-photons that exceed π rad can be used to implement two-qubit quantum logic gates. For a conventional XPM scheme, the Kerr nonlinearity responsible for XPM is too small for appreciable phase shifts to be achieved with low intensity optical fields. However, Electromagnetically Induced Transparency (EIT) can increase this nonlinearity by several orders of magnitude. This thesis discusses the experimental construction of a laser-atomic system capable of EIT modulated XPM. This includes construction of a rubidium magneto-optical trap (RbMOT), characterization of this RbMOT, demonstration of EIT in the RbMOT, and a system capable of detecting optical phase shifts produced by EIT. The talk will conclude with an outlook on further implementations to the experiment that will increase this nonlinearity such that phase shifts at the single-photon level are possible. | 76 pages
Two-photon vapor cell-based optical clocks are strong candidates for next-generation portable atomic standards, offering simplicity, compactness, and high performance. Their narrow clock transitions with counter-propagating beams enable first-order Doppler-free operation. However, systematic perturbations such as the AC Stark shift, temperature-induced shift, and drifts resulting from the laser system pose challenges cause instabilities to medium- to long-term performance. This paper provides a comprehensive overview of Rb two-photon vapor cell optical standards, focusing on the long-term performance-limiting effects and potential mitigation strategies, aiming for clock stabilities better than 1 × 10−15 over the averaging time of a day and beyond.