2025/05/22 by Akhil Ayyadevara, Ayyadevara, Akhil, Anand Prakash +8 · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Charge (physics) #Cold Atom Physics and Bose-Einstein Condensates #Coulomb #Dynamics (music) #Electronic and Structural Properties of Oxides #Field (mathematics) #Ion #Lattice (music) #Mesoscopic physics #Metastability #Non-equilibrium thermodynamics #Phase transition #Physics of Superconductivity and Magnetism #Symmetry (geometry) #Variety (cybernetics) #Work (physics)
paper · pdf · doi:10.1103/2rs1-c5r1
openalex publication_date 2026/02/09 · openalex created_date 2026/02/10 · openalex updated_date 2026/03/20
Interacting many-particle systems can self-organize into a rich variety of crystalline structures. While symmetry provides a powerful framework for predicting whether transitions between crystal states are continuous or discontinuous, collective lattice dynamics offer complementary insights into the microscopic mechanisms that drive these transitions. Trapped laser-cooled ions present a pristine and highly controllable system for studying this interplay of symmetry and dynamics. Here, we use real-time fluorescence imaging while deforming the trap potential to observe a variety of structural transitions in three-dimensional (3D), unit-cell-like ion clusters. We identify a set of unexplored transitions signaled by parity-odd octupole order parameters and probe their distinct dynamical signatures. Our experiments reveal the softening of a collective Higgs-like mode, indicating spontaneous symmetry breaking, hysteresis resulting from a catastrophe where a metastable state vanishes abruptly, and stochastic switching between metastable states of distinct symmetries. We also uncover a remarkable coincidence of symmetry-breaking and discontinuous transitions, analogous to a thermodynamic triple point. Our results establish 3D trapped-ion clusters as a versatile platform for engineering complex potential energy landscapes, opening avenues for studying collective phenomena such as geometric frustration with multipolar orders and the stochastic kinetics of rare events in exotic mesoscopic settings.