Tunable Anomalous Diffusion in Subrecoil-Laser-Cooled Atoms

The control of atomic motion through laser cooling has revolutionized quantum technologies, enabling applications ranging from quantum computing to precision metrology. However, the spatial spreading of subrecoil-laser-cooled atoms – crucial for understanding cooling mechanisms and atomic confinement – remains largely unexplored. Here, we analyze anomalous diffusion in subrecoil-laser-cooled atoms, where a velocity-dependent fluorescence rate $R(v)\propto \mathrm{\mid }v{\mathrm{\mid }}^{\alpha }$ governs transport properties. By tuning $\alpha$, we uncover transitions between normal, subdiffusive, and superdiffusive regimes. Notably, at $\alpha =3\mathrm{/}2$, diffusion is minimized, leading to optimal atomic confinement. These findings advance the understanding of anomalous transport in laser-cooled systems and offer new avenues for precise control of atomic motion.