2025/02/11 by G. Labeyrie, Labeyrie, G., Ivor Krešić +5 · 2 citations
Physics and Astronomy · #Atomic Physics (physics.atom-ph) #FOS: Physical sciences #Laser-Matter Interactions and Applications #Nonlinear Photonic Systems #Optics (physics.optics) #Pattern Formation and Solitons (nlin.PS) #Photonic Crystals and Applications
paper · doi:10.48550/arxiv.2502.07554
openalex publication_date 2025/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Cold atomic clouds constitute highly resonant nonlinear optical media, whose refractive index can be easily tuned via the light frequency. When subjected to a retro-reflected laser beam and under appropriate conditions, the cloud undergoes spontaneous symmetry breaking and spatial patterns develop in the transverse cross-section of the beam. We investigate the impact of the sign of the light detuning from the atomic resonance on these patterns, thus directly comparing pattern formation for self-focusing and self-defocusing nonlinearities. Our observations emphasize the need for a ''diffractively thick'' medium description of the light-cloud interaction, where diffraction and nonlinear propagation inside the sample are taken into account.