Leanhardt A E, Pasquini T A, Saba M, Schirotzek A, Shin Y, Kielpinski D, Pritchard D E, Ketterle W
Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science. 2003 Sep 12;301(5639):1513-5. doi: 10.1126/science.1088827.
Spin-polarized gaseous Bose-Einstein condensates were confined by a combination of gravitational and magnetic forces. The partially condensed atomic vapors were adiabatically decompressed by weakening the gravito-magnetic trap to a mean frequency of 1hertz, then evaporatively reduced in size to 2500 atoms. This lowered the peak condensate density to 5 x 10(10) atoms per cubic centimeter and cooled the entire cloud in all three dimensions to a kinetic temperature of 450 +/- 80 picokelvin. Such spin-polarized, dilute, and ultracold gases are important for spectroscopy, metrology, and atom optics.
自旋极化的气态玻色-爱因斯坦凝聚体由引力和磁力共同约束。通过减弱重力磁阱至平均频率1赫兹，对部分凝聚的原子蒸汽进行绝热减压，然后通过蒸发使其尺寸减小至2500个原子。这将凝聚体的峰值密度降低至每立方厘米5×10(10)个原子，并将整个云团在所有三个维度上冷却至450±80皮开尔文的动力学温度。这种自旋极化、稀薄且超冷的气体对于光谱学、计量学和原子光学很重要。
