Building cold atomic quantum sensors with photonic structures promise to miniaturize the apparatus that could eventually lead to portable devices. To prepare atoms in photonic platforms to a temperature that can be applied as a sensor requires adopting free-space laser cooling in space-constrained photonic structures. Here, we demonstrate in-fiber Λ-enhanced gray molasses and delta-kick cooling to cool atoms inside a 22-cm-long negative curvature hollow-core photonic crystal fiber from 32 μK to sub-μK in 4 ms. The in-fiber cooling overcomes the inevitable heating during the atom loading process and allows a shallow guiding optical potential to minimize decoherence. We employ these cold atoms in an inertia sensitive atom interferometer optically guided inside a hollow-core photonic crystal fiber with an interferometer time of 20 ms. The result improves the previous fiber guided atom interferometer sensitivity by three orders of magnitude. Our results permit bringing atoms close to source fields for sensing and could lead to compact inertial quantum sensors with a sub-millimeter resolution.
|Presenter name||Leong, Wui Seng|