Temperatures near the recoil limit in an atomic funnel

Abstract

We report on an improved atomic funnel with transverse velocities near the recoil limit. Its central element is an atomic funnel, strongly tilted against the initial atomic beam axis, deflecting, compressing and cooling a laser decelerated metastable neon beam. In spite of a strong magnetic field gradient at 350 G/cm polarisation gradient cooling in the final section of the funnel leads to transverse temperatures far below the Doppler limit. These results were achieved for unusual small laser detunings, which cannot be explained by standard sub-Doppler theory.