38 research outputs found
Loading and cooling in an optical trap via hyperfine dark states
We present an optical cooling scheme that relies on hyperfine dark states to enhance loading and cooling atoms inside deep optical dipole traps. We demonstrate a sevenfold increase in the number of atoms loaded in the conservative potential with strongly shifted excited states. In addition, we use the energy selective dark state to efficiently cool the atoms trapped inside the conservative potential rapidly and without losses. Our findings open the door to optically assisted cooling of trapped atoms and molecules which lack the closed cycling transitions normally needed to achieve low temperatures and the high initial densities required for evaporative cooling
Velocimetry, cooling and rotation sensing by cold-atom matterwave interferometry
Interferometric measurement of an atom’s velocity allows, by tailoring the impulse imparted by the matterwave-splitting laser pulses, a velocity-dependent force that cools an atomic sample. Differential measurement reveals the sample’s acceleration and rotation
OH detection by absorption of frequency-doubled diode laser radiation at 308nm
Radiation at 308 nm has been obtained by frequency doubling the output of a commercial diode laser cooled to 165 K. A single pass through a crystal of LiIO3 converted 1 mW of 616 nm radiation to 50 pW of UV, and this was used to detect the OH radical in absorption in a flow tube. Possible extensions of the method for detection of OH in the atmosphere are discussed
Scattering theory of cooling in optomechanical systems
We present a one-dimensional scattering theory, arising from the optomechanical coupling of the motional degree of freedom of scatterers to the electromagnetic field. Multiple scattering to all orders is taken into account, and the result is a versatile model that can be used to describe a wealth of effects, including optical molasses and novel interactions between atoms and cavities that could potentially lead to optical cooling mechanisms applicable to a wide range of species