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arXiv · 0710.2499

Dynamical instability of the XY spiral state of ferromagnetic condensates

R. W. Cherng·V. Gritsev·D. M. Stamper-Kurn·E. Demler
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Abstract

We calculate the spectrum of collective excitations of the XY spiral state prepared adiabatically or suddenly from a uniform ferromagnetic F=1 condensate. For spiral wavevectors past a critical value, spin wave excitation energies become imaginary indicating a dynamical instability. We construct phase diagrams as functions of spiral wavevector and quadratic Zeeman energy.

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R. W. Cherng, V. Gritsev, D. M. Stamper-Kurn, E. Demler. 2007-10-12. Dynamical instability of the XY spiral state of ferromagnetic condensates. https://doi.org/10.1103/physrevlett.100.180404

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