Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose-Einstein condensate

Article

关键词: DYNAMICS;    DOMAINS;    VORTEX;    ANALOG;    PHASE;   

DOI  :  10.1038/nature05094

来源: SCIE

【 摘 要 】

A central goal in condensed matter and modern atomic physics is the exploration of quantum phases of matter - in particular, how the universal characteristics of zero-temperature quantum phase transitions differ from those established for thermal phase transitions at non-zero temperature. Compared to conventional condensed matter systems, atomic gases provide a unique opportunity to explore quantum dynamics far from equilibrium. For example, gaseous spinor Bose - Einstein condensates(1-3) ( whose atoms have non-zero internal angular momentum) are quantum fluids that simultaneously realize superfluidity and magnetism, both of which are associated with symmetry breaking. Here we explore spontaneous symmetry breaking in Rb-87 spinor condensates, rapidly quenched across a quantum phase transition to a ferromagnetic state. We observe the formation of spin textures, ferromagnetic domains and domain walls, and demonstrate phase-sensitive in situ detection of spin vortices. The latter are topological defects resulting from the symmetry breaking, containing non-zero spin current but no net mass current(4).

【 授权许可】

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