The coupling of a particle to its surroundings enables important condensed-matter phenomena such as the formation of polarons in solid-state and low-temperature systems, and is a central concept in the study of decoherence and dissipation. This project focuses on the experimental study of such coupled systems using mixtures of ultracold bosonic atoms trapped in an optical lattice. Using a hyperfine-ground state mixture of bosonic atoms in state-dependent optical lattices allows for the immersion of localized atoms in a bosonic background medium. One of the goals of the projectis to detect polaronic energy shifts and clustering spectroscopically in the limit of strong interactions. Another goal is to study the dynamics of a localized, driven atomic spin coupled to a bosonic superfluid as a simple realization of a spin-boson model for the study of quantum dissipative effects. Using state-dependent potentials as a manipulation tool, a third goal is to study out-of-equilibrium dynamics of one-dimensional spin mixtures with the possibility of observing spin-charge separation.
The elucidation of behavior specific to complex materials will have the potential for broad scientific and technological impact that can ultimately benefit society. The project will advance the state of the art of quantum-gas research in this direction, and it will also provide scientific and technical training to both graduate and undergraduate students who will gain proficiency in the enabling technologies of lasers and optics, ultrahigh vacuum, and electronics.
