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arXiv · 1007.2342

Spontaneous breaking of spatial and spin symmetry in spinor condensates

M. Scherer·B. Lücke·G. Gebreyesus·O. Topic·F. Deuretzbacher·W. Ertmer·L. Santos·J. J. Arlt·C. Klempt
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Abstract

Parametric amplification of quantum fluctuations constitutes a fundamental mechanism for spontaneous symmetry breaking. In our experiments, a spinor condensate acts as a parametric amplifier of spin modes, resulting in a twofold spontaneous breaking of spatial and spin symmetry in the amplified clouds. Our experiments permit a precise analysis of the amplification in specific spatial Bessel-like modes, allowing for the detailed understanding of the double symmetry breaking. On resonances that create vortex-antivortex superpositions, we show that the cylindrical spatial symmetry is spontaneously broken, but phase squeezing prevents spin-symmetry breaking. If, however, nondegenerate spin modes contribute to the amplification, quantum interferences lead to spin-dependent density profiles and hence spontaneously-formed patterns in the longitudinal magnetization.

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M. Scherer, B. Lücke, G. Gebreyesus, O. Topic, F. Deuretzbacher, W. Ertmer, L. Santos, J. J. Arlt, C. Klempt. 2010-07-14. Spontaneous breaking of spatial and spin symmetry in spinor condensates. https://doi.org/10.1103/physrevlett.105.135302

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