Browsing by Author "Tollett, Jeffrey John"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item A permanent magnet trap for cold atoms(1995) Tollett, Jeffrey John; Hulet, Randall G.Approximately$4\times10\sp8$ ground state lithium atoms have been confined in a non-zero magnetic field minimum produced by six permanent magnets in an Ioffe configuration. These atoms have a kinetic temperature of 1.1 mK and a peak density of $8\times10\sp9$ cm$\sp{-3}$ The trapped atom lifetime is 240 seconds, limited by collisions with background gas. The tightly confining fields generated through the use of permanent magnets create a trap which is an excellent environment for the study of quantum statistical effects, atomic collisions, and other ultra-low temperature phenomena.Item The force on an atom moving in an intense standing wave(1991) Tollett, Jeffrey John; Hulet, Randall G.Atoms moving in an intense, near resonant standing wave (SW) experience a force along the direction of the SW. This force has been investigated by observing its effect on the transverse velocities of atoms in a thermal beam. When the standing wave is tuned above resonance the atomic beam is collimated and has an increased intensity at the center of the beam. Below resonance, the SW anti-collimates the atomic beam, reducing the central intensity. These effects are due to the interaction between the induced atomic dipole and the inhomogeneous field of the SW. Further investigation shows structure in the transverse velocity distribution of the atomic beam. This structure is due to multiphoton (Doppleron) resonances in the force. Calculations reproduce the dipole force and multiphoton resonance effects and are in good agreement with the data.