FOLIO (Fluids Of Light in hollow-core fiber mIcrO-cells) is an ambitious research project coordinated by Quentin Glorieux. Running for 48 months, its goal is to explore the exciting potential of creating and studying new states of light through the development of an innovative fiber-based integrated device combining atoms and photonics.
Photons are excellent information carriers but generally do not interact. Atoms do interact, but are more difficult to manipulate and lack the quantum optics toolbox for detecting quantum fluctuations and entanglement. Many approaches have been proposed to combine the two, and fluids of light have emerged as promising candidates to bridge the gap between quantum gases and quantum optics.
Current fluid-of-light platforms using semiconductor microcavities or dye-filled cavities are driven-dissipative, limiting their ability to generate new states of light to a narrow subset that is robust to losses. In 2018, the PI’s group introduced an alternative approach based on the analogy between the Gross-Pitaevskii equation and the paraxial propagation of monochromatic light in a nonlinear medium (a rubidium vapor cell). This system features low loss and tunable photon-photon interactions.
However, these paraxial experiments are limited by short interaction lengths and weak nonlinearities. Moreover, cold atom and quantum optics labs require complex UHV setups, which are bulky and expensive.
FOLIO aims to overcome these limitations by developing a new experimental platform based on:
This platform creates a bridge between cold atom quantum gases and photonic systems.
By inducing photon-photon interactions and confining light in low-dimensional geometries (1D and 2D), FOLIO will create fluids of light capable of undergoing phase transitions, forming vortices, or reaching complex molecular-like quantum states.
The FOLIO approach is based on two innovations:
HCPCFs serve both as micro-containers for alkali vapors and as optical waveguides with tailored mode content, enabling a versatile and high-performance atom–light coupling platform. The system can be hermetically sealed to create a Photonic Micro-cell® (PMC), patented by GLOPhotonics.
FOLIO is a collaborative effort between three complementary partners:
The consortium is structured for iterative feedback between experimental development, material design, and fundamental physics.
FOLIO is organized around three major goals:
Fabrication of a rubidium-filled Photonic Micro-cell® (PMC)
– HCPCF with controlled mode content, anti-relaxation coating, and fiber-pigtailed interfaces.
– Led by GLOPhotonics with support from GPPMM (WP1)
Study of weakly interacting photon fluids with hot vapors
– Observing long-time dynamics in 1D and 2D using HCPCFs
– Led by LKB (WP2)
Demonstration of strongly interacting photon fluids using cold atoms
– Creating a cold atom cloud inside a fiber and inducing giant nonlinearities via EIT
– Led by GPPMM with support from LKB and GLO (WP3)
Quentin Glorieux
Laboratoire Kastler Brossel – Sorbonne Université
📧 quentin.glorieux@lkb.upmc.fr