Quantum Carpets of Higgs Quasiparticles in a Supersolid

Abstract

Supersolids formed from dipolar Bose Einstein condensates (BECs) exhibit spontaneous density modulation while maintaining global phase coherence. This state of matter supports gapped amplitude (Higgs) excitations featuring a quadratic dispersion relation. While Higgs modes are typically strongly damped due to coupling with other amplitude and phase modes, imposing an experimentally realistic toroidal geometry allows us to numerically study the time evolution and dispersion of a localized Higgs quasiparticle excitation, with minimal residual coupling to sound modes. Strikingly, the quadratic dispersion leads to the occurrence of (fractional) revivals, similar to those seen in the optical Talbot effect or the so-called quantum carpets. The revival times provide a novel method for determining the effective mass of the Higgs quasiparticle through a nonspectroscopic approach. These results pave the way for further studies of coherent Higgs dynamics and mutual interactions between Higgs quasiparticle.