We observe counter-intuitive spin segregation in an inhomogeneous sample of ultra-cold, noncondensed Rubidium atoms in a magnetic trap. We use spatially selective microwave spectroscopy to verify a model that accounts for the differential forces on two internal spin states. In any simple understanding of the cloud dynamics, the forces are far too small to account for the dramatic transient spin polarizations observed. The underlying mechanism remains to be elucidated.

We designed and constructed a simplified experimental system to create a Bose-Einstein condensate in 87 Rb. Our system has several novel features including a mechanical atom transfer mechanism and a hybrid Ioffe-Pritchard magnetic trap. The apparatus has been designed to consistently produce a stable condensate even when it is not well optimized.

The release of stored elastic energy often drives rapid movements in animal systems, and plant components employing this mechanism should be able to move with similar speed. Here we describe how the flower stamens of the bunchberry dogwood (Cornus canadensis) rely on this principle to catapult pollen into the air as the flower opens explosively. Our high-speed video observations show that the flower opens in less than 0.5 ms--to our knowledge, the fastest movement so far recorded in a plant.