Probing quantum floating phases in Rydberg atom arrays
Jin Zhang, Sergio Cantu, Fangli Liu, Alexei Bylinskii, Boris Braverman, Florian Huber, Jesse Amato-Grill, A. Ya. Lukin, Nathan Gemelke, Alexander Keesling, Sheng-Tao Wang, Yannick Meurice, Shan-Wen Tsai
Abstract
The floating phase, a critical incommensurate phase, has been theoretically predicted as a potential intermediate phase between crystalline ordered and disordered phases. In this study, we investigate the different quantum phases that arise in ladder arrays comprising up to 92 neutral-atom qubits and experimentally observe the emergence of the quantum floating phase. We analyze the site-resolved Rydberg state densities and the distribution of state occurrences. The site-resolved measurement reveals the formation of domain walls within the commensurate ordered phase, which subsequently proliferate and give rise to the floating phase with incommensurate quasi-long-range order. By analyzing the Fourier spectra of the Rydberg density-density correlations, we observe clear signatures of the incommensurate wave order of the floating phase. Furthermore, as the experimental system sizes increase, we show that the wave vectors approach a continuum of values incommensurate with the lattice. Our work motivates future studies to further explore the nature of commensurate-incommensurate phase transitions and their non-equilibrium physics. The critical floating phase can bridge crystalline orders and the disordered phase. Here, the authors experimentally observe the quantum floating phase in neutral atom qubit arrays, revealing domain walls and incommensurate quasi long-range order, and analyse its emergence via Fourier spectroscopy.