TY - JOUR
AU - W. Morong
AU - Sean Muleady
AU - Itamar Kimchi
AU - W. Xu
AU - Rahul Nandkishore
AU - Ana Maria Rey
AU - B. DeMarco
AB - Understanding the collective behavior of quantum, many-particle interacting systems is a central problem in modern science. The disordered Fermi-Hubbard model (DFHM) is a key tool for addressing this challenge in the context of strongly correlated electronic solids. This paradigm, which describes interacting particles that tunnel between sites of a crystalline lattice, incorporates disorder to represent the influence of impurities and imperfections on material properties. Tremendous progress has been made on characterizing how disorder and interactions lead to transitions between low-temperature, equilibrium states. However, the extreme complexity associated with out-of-equilibrium behavior, especially in higher dimensions, has made uncovering organizing principles for the dynamical properties of the DFHM model a formidable challenge. Here we show that the relaxation dynamics of doublon excitations (composed of doubly occupied--empty site pairs) in the three-dimensional DFHM model can be understood as a competition between disorder-enhanced quantum resonances and suppressed diffusive transport. Using interaction-quench measurements on a quantum simulator implemented by cooling fermionic 40K atoms in a cubic optical lattice, we find two regimes of doublon decay distinguished by suppression or enhancement of relaxation for increasing disorder. A simple reaction--diffusion model provides an analytical description, which is consistent with the onset of localization for strong disorder. This approach is augmented by developing an approximate numerical technique that shows excellent agreement with the measurements. Our results demonstrate the power of quantum simulators to illuminate the fundamental behavior of complex many-particle quantum dynamics and to provide a pathway for developing computational tools and theoretical understanding, even in regimes that hamper exact solutions.
BT - Physical Review Research
DA - 2021-01
DO - 10.1103/PhysRevResearch.3.L012009
IS - 1
N2 - Understanding the collective behavior of quantum, many-particle interacting systems is a central problem in modern science. The disordered Fermi-Hubbard model (DFHM) is a key tool for addressing this challenge in the context of strongly correlated electronic solids. This paradigm, which describes interacting particles that tunnel between sites of a crystalline lattice, incorporates disorder to represent the influence of impurities and imperfections on material properties. Tremendous progress has been made on characterizing how disorder and interactions lead to transitions between low-temperature, equilibrium states. However, the extreme complexity associated with out-of-equilibrium behavior, especially in higher dimensions, has made uncovering organizing principles for the dynamical properties of the DFHM model a formidable challenge. Here we show that the relaxation dynamics of doublon excitations (composed of doubly occupied--empty site pairs) in the three-dimensional DFHM model can be understood as a competition between disorder-enhanced quantum resonances and suppressed diffusive transport. Using interaction-quench measurements on a quantum simulator implemented by cooling fermionic 40K atoms in a cubic optical lattice, we find two regimes of doublon decay distinguished by suppression or enhancement of relaxation for increasing disorder. A simple reaction--diffusion model provides an analytical description, which is consistent with the onset of localization for strong disorder. This approach is augmented by developing an approximate numerical technique that shows excellent agreement with the measurements. Our results demonstrate the power of quantum simulators to illuminate the fundamental behavior of complex many-particle quantum dynamics and to provide a pathway for developing computational tools and theoretical understanding, even in regimes that hamper exact solutions.
PY - 2021
SE - L012009
EP - L012009
T2 - Physical Review Research
TI - Disorder-controlled relaxation in a three-dimensional Hubbard model quantum simulator
UR - https://link.aps.org/doi/10.1103/PhysRevResearch.3.L012009
VL - 3
ER -