Topology and Emergence with Ultracold Atoms and Molecules
Abstract
Quantum degenerate atoms and molecules trapped by lasers offer environments essentially free from dirt, impurities, and defects that typically plague solid-state systems, allowing very precise characterization by "clean" many-body models. The observation of novel quantum correlated phases of matter offers the potential for profound impact since these systems provide paradigmatic tools for further studies and test beds for macroscopic quantum phenomena. We seek to construct theories of ultracold atomic and molecular gases under two central themes: topological states and flat-band emergent states. In both cases we will examine viability for observing these states in the laboratory. We propose to validate engineering of Hamiltonians for emergent Fermi surfaces in flat MoirŽ bands; Hopf superfluids; and the realization of plaquette Mott insulators. The connection between experiments in graphene and the non-trivial physics of flat MoirŽ bands is currently of urgent interest. We propose to construct setups where ultracold atoms and molecules in suitably designed optical lattices will help shed light on the role of interactions in flat MoirŽ bands. We will numerically simulate limits to search for regimes where interactions generate emergent Fermi surfaces and possibly even superconductors. We also propose to construct a new state of matter: a Hopf superfluid. Here our central goal is to propose a route to use Laguerre-Gaussian beams to impose topological defects with non-trivial Hopf index hosting robust Majorana modes in an otherwise ordinary $s$-wave superfluid of ultracold fermions. We will analyze realizable models of attractive two-dimensional fermions. Chiral currents also signal topological states. We propose to examine adiabatic state preparation protocols, the low energy excitations, and the observable chiral domains in the context of plaquette Mott insulators for bosons and fermions and a chiral density wave state for fermions. These states should be experimentally accessible precursors to quantum Hall states using atoms and molecules in optical lattices with synthetic flux. Our overall goal is to foster the identification of novel states of matter with ultracold atomic and molecular gases derived from interaction of direct importance to ongoing Army research efforts.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 12, 2022
- Source ID
- W911NF2210247
Entities
People
- V W Scarola
Organizations
- Army Contracting Command
- United States Army
- Virginia Tech