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arXiv · 2206.08551

Stability of a flattened dipolar binary condensate: emergence of the spin roton

Au-Chen Lee·D. Baillie·P. B. Blakie
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Abstract

We develop theory for a two-component miscible dipolar condensate in a planar trap. Using numerical solutions and a variational theory we solve for the excitation spectrum and identify regimes where density- and spin-roton excitations are favored. We characterize the various instabilities that can emerge in this system over a wide parameter regime and present results for the stability phase diagram. Importantly this allows us to identify the parameter regimes where a novel roton-immiscibility transition can occur, driven by the softening of the spin roton excitation.

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Au-Chen Lee, D. Baillie, P. B. Blakie. 2022-06-17. Stability of a flattened dipolar binary condensate: emergence of the spin roton. https://doi.org/10.1103/physrevresearch.4.033153

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