Compressibility and speeds of sound across the superfluid to supersolid phase transition of an elongated dipolar gas

@article{blakie2023cas,
      title={Compressibility and speeds of sound across the superfluid to supersolid phase transition of an elongated dipolar gas}, 
      author={P. B. Blakie and L. Chomaz and D. Baillie and F. Ferlaino},
      year={2023},
	  month = {Jun},
	abstract = {We investigate the excitation spectrum and compressibility of a dipolar Bose-Einstein condensate in an infinite
tube potential in the parameter regime where the transition between superfluid and supersolid phases occurs. Our
study focuses on the density range in which crystalline order develops continuously across the transition. Above
the transition the superfluid shows a single gapless excitation band, phononic at small momenta and with a
roton at a finite momentum. Below the transition, two gapless excitations branches (three at the transition point)
emerge in the supersolid. We examine the two gapless excitation bands and their associated speeds of sound
in the supersolid phase. Our results show that the speeds of sound and the compressibility are discontinuous
at the transition, indicating a second-order phase transition. These results provide valuable insights into the
identification of supersolid phenomena in dipolar quantum gases and the relationship to supersolidity in spinorbit coupled gases},
      eprint={2306.04794},
      archivePrefix={arXiv},
      primaryClass={cond-mat.quant-gas},
	  journal={arXiv:2306.04794},
	  arXiv = {http://arxiv.org/abs/2306.04794},
	url = {http://arxiv.org/abs/2306.04794},
	doi = {https://doi.org/10.1103/PhysRevResearch.5.033161}
}