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  • Letter
  • Open Access

Interaction shift of the Bose-Einstein condensation temperature in a dipolar gas

Milan Krstajić, Jiří Kučera, Lucas R. Hofer, Gavin Lamb, Péter Juhász, and Robert P. Smith*

  • *Contact author: robert.smith@physics.ox.ac.uk
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Phys. Rev. A 111, L051303 – Published 19 May, 2025

DOI: https://doi.org/10.1103/PhysRevA.111.L051303

Abstract

We report measurements of the Bose-Einstein condensate critical temperature shift due to dipolar interactions, employing samples of ultracold erbium atoms which feature significant (magnetic) dipole-dipole interactions in addition to tunable contact interactions. Using a highly prolate harmonic trapping potential, we observe a clear dependence of the critical temperature on the orientation of the dipoles relative to the trap axis. Our results are in good agreement with mean-field theory for a range of contact interaction strengths. This work creates an opportunity for further investigations into beyond-mean-field effects and the finite-temperature phase diagram in the more strongly dipolar regime where supersolid and droplet states emerge.

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Phys. Rev. A 111, L051303– Published 19 May, 2025
  • Received 31 January 2025
  • Accepted 5 May 2025
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