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arXiv · 1501.06830

Spontaneous PT symmetry breaking of a ferromagnetic superfluid in a gradient field

Thomas Vanderbruggen·Silvana Palacios·Simon Coop·Natali Martinez de Escobar·Morgan Mitchell
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Abstract

We consider the interaction of a ferromagnetic spinor Bose-Einstein condensate with a magnetic field gradient. The magnetic field gradient realizes a spin-position coupling that explicitly breaks time-reversal symmetry T and space parity P, but preserves the combined PT symmetry. We observe using numerical simulations, a first-order phase transition spontaneously breaking this re-maining symmetry. The transition to a low-gradient phase, in which gradient effects are frozen out by the ferromagnetic interaction, suggests the possibility of high-coherence magnetic sensors unaffected by gradient dephasing.

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Thomas Vanderbruggen, Silvana Palacios, Simon Coop, Natali Martinez de Escobar, Morgan Mitchell. 2015-01-27. Spontaneous PT symmetry breaking of a ferromagnetic superfluid in a gradient field. https://doi.org/10.1209/0295-5075/111/66001

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