Research project is (co) funded by the Slovenian Research Agency.
UL Member: Faculty of Mathematics and Physics
Code: NESY
Project: Nonergodicity from Exotic Symmetries (NESY)
Period: 1. 1. 2025 - 31. 12. 2028
Range per year: 2 FTE
Head: Lenart Zadnik
Research activity: Natural sciences and mathematics
Project description:
Quantum technologies rely on quantum coherence and nonstationarity preceding thermalization, making the study of nonthermal and nonergodic phenomena crucial. A useful framework for exploring exotic nonergodicity are kinetically constrained models, originally devised as stochastic descriptions of slow dynamics and relaxation in viscous fluids and glasses. Given the diversity of the nonthermal phenomena that they support, the materials described by quantum kinetically constrained models may host robust quantum properties. They thus have the potential to enhance the durability of quantum technologies. Studying kinetically constrained models could uncover new symmetries underlying the exotic nonergodic phenomena and enable the classification of quantum materials with enhanced coherence, similar to the periodic table of topological phases of matter. We aim to investigate how nonergodic phenomena in kinetically constrained models emerge from exotic symmetries, develop their hydrodynamic description, and examine the interplay between nonergodicity and dissipation.
In this project we will (1) explore the origins of exotic nonergodic phenomena such as Hilbert-space fragmentation, quantum many-body scars, and dynamical symmetries in kinetically constrained models in which such phenomena coexist. Moreover, we will study how the coexistent exotic nonergodic phenomena are related to the symmetries that give rise to integrability in exactly-solvable kinetically constrained models. (2) We will develop tools to identify nonequilibrium symmetry-protected topological order supported by the so-called semilocal conserved quantities. To achieve this, we will analyze Ruelle-Pollicott spectra and quantum information measures in kinetically constrained models that exhibit out-of-equilibrium semilocal order. (3) One of our aims is also to understand the emergence of glassy relaxation through the lens of Hilbert-space fragmentation in the strongly-coupled lattice models of magnetism. (4) Finally, we will investigate the large-scale hydrodynamic picture of exotic nonergodic phenomena, and (5) study their stability under dissipation.
