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  • Letter
  • Open Access

Decoupled sound and amplitude modes in trapped dipolar supersolids

J. Hertkorn1,*, P. Stürmer2, K. Mukherjee2, K. S. H. Ng1, P. Uerlings1, F. Hellstern1, L. Lavoine1, S. M. Reimann2, T. Pfau1 et al.

R. Klemt1,†

  • 15. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
  • 2Division of Mathematical Physics and NanoLund, LTH, Lund University, Box 118, SE-221 00 Lund, Sweden

  • *Contact author: j3h@mit.edu
  • †Contact author: rklemt@pi5.physik.uni-stuttgart.de
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Phys. Rev. Research 6, L042056 – Published 5 December, 2024

DOI: https://doi.org/10.1103/PhysRevResearch.6.L042056

Abstract

We theoretically investigate elementary excitations of dipolar quantum gases across the superfluid to supersolid phase transition in a toroidal trap. We show how decoupled first sound, second sound, and Higgs modes emerge by following their origin from superfluid modes across the transition. The structure of these excitations reveals the interplay between crystal and superfluid oscillations. Our results unify previous notions of coupled Goldstone and Higgs modes in harmonic traps, allowing us to establish a correspondence between excitations of trapped and infinitely extended supersolids. We propose protocols for selectively probing these sound and amplitude modes, accessible to state-of-the-art experiments.

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Phys. Rev. Research 6, L042056– Published 5 December, 2024
  • Received 10 April 2024
  • Revised 28 June 2024
  • Accepted 21 October 2024
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