As being superfluid, particle current in BEC is irrotational and this makes that its respondence to rotation is different from rotating as a whole for usual fluid and is to form a vortex or vortex lattice.

• 作为超流体，BEC中的粒子流是无旋的，这使得它对旋转的响应异于普通流体的整体转动而产生涡旋或涡旋晶格。