We study ^(87)Rb Bose-Einstein condensation(BEC) loading into the pulse of the one-dimensional(1D) optical lattice experimentally.The lattice is turned on abruptly,held constant for a variable time,and then turned off abruptly.The measurement of the depth of the optical lattice is obtained by Kapitza-Dirac scattering.The temporal matter-wave-dispersion Talbot effect with ^(87)Rb BEC is observed by applying a pair of pulsed standing waves(as pulsed phase gratings) with the separation of a variable delay.
We report the experimental achievement of ^(87)Rb Bose-Einstein condensation in a magnetic trap with microwave and radio frequency(RF) induced evaporation.Evaporative cooling is realized by using 6.8 GHz microwave radiation driving the ^(87)Rb atoms to transit from the ground-state hyperfine state |F=2,m_F= 2〉to |F=l,m_F=1〉.Compared with RF-induced evaporation,^(87)Rb atoms are hardly to achieve pure condensate by microwave evaporation cooling due to the effect of atoms in the |F=1,m_F=1〉state being pumped back into the trapping |F=2,m_F=1〉state.
We report the experimental preparations of the absolute ground states of 87Rb and 40K atoms (|F = 1, mF = 1 ) + |F = 9/2, rnF : -9/2)) by means of the radio-frequency and microwave adiabatic rapid passages, and the observation of magnetic Feshbach resonances in an ultracold mixture of bosonic STRb and fermionic 40K atoms between 0 T and 6.0 × 10^-2 T, including 7 homonuclear and 4 heteronuclear Feshbach resonances. The resonances are identified by the abrupt trap loss of atoms induced by the strong inelastic three-body collisions. These Feshbach resonances should enable the experimental control of interspecies interactions.
We create a Bose-Einstein condensate (BEC) of 87Rb atoms by runaway evaporative cooling in an optical trap. Two crossed infrared laser beams with a wavelength of 1064 nm are used to form an optical dipole trap. After precooling the atom samples in a quadrupole-Ioffe configuration (QUIC) trap under 1.5 #K by radio-frequency (RF) evaporative cooling, the samples are transferred into the center of the glass cell, then loaded into the optical dipole trap with 800 ms. The pure condensate with up to 1.5× 10^5 atoms is obtained over 1.17 s by lowering the power of the trap beams.