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arXiv:2603.29738

Phase diagram of rotating Bose-Einstein condensates trapped in power-law and hard-wall potentials

G. M. Kavoulakis

cond-mat.quant-gasphysics.atom-phquant-phSubmitted Mar 31, 2026• Announced Apr 1, 2026• 0 citations• Revised Jul 7, 2026 (v2)

v1 · Mar 31, 2026 v2 · Jul 7, 2026

Abstract

We investigate the rotational phase diagram of a quasi-two-dimensional, weakly-interacting Bose-Einstein condensate confined in power-law and in hard-wall trapping potentials. For weak interactions, the system undergoes discontinuous transitions between multiply-quantized vortex states as the rotation frequency of the trap increases. In contrast, stronger interactions induce continuous phase transitions toward mixed states involving both singly and multiply-quantized vortex states. A central result is the qualitative (and experimentally observable) difference between power-law and hard-wall confinement: In hard-wall traps, the leading instability always involves states with nonzero density at the trap center, whereas in power-law traps the density vanishes as the rotation frequency increases. The two different types of confinement give rise to scaling properties in the derived phase diagrams.

Journal reference: Phys. Rev. A 114, 013308 (2026)
Comments: Published version, 12 pages, 8 figures

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