AN OPTO-ELECTRIC TRAP FOR COLD ATOMS

We present a new type of conservative trap for cold atoms: a static el ectric field creates a position-dependent Stark potential to compensat e gravity and a far-off-resonance laser beam provides transverse confi nement. We demonstrate this Opto-Electric Trap (OET) on cesium atoms, using a ring electrode at 12 kV and a Ti-sapphire laser. Loaded from a magneto-optical trap, up to 2.5 . 10(5) atoms are captured in the OET . The 1/e lifetime is similar to 1 s, presently limited by collisions with the background gas. This trap is well suited for subrecoil laser cooling and evaporative cooling of confined atoms.