Spin, Bose, and Non-Fermi Liquid Metals in Two Dimensions: Accessing via Multi-Leg Ladders

Understand

Characterizing and accessing quantum phases of itinerant bosons or fermions in two dimensions (2D) that exhibit singular structure along surfaces in momentum space but have no quasi-particle description remains as a central challenge in the field of strongly correlated physics.

• Fortuitously, signatures of such 2D strongly correlated phases are expected to be manifest in quasi-one-dimensional "$N$-leg ladder" systems.
• The ladder discretization of the transverse momentum cuts through the 2D surface, leading to a quasi-1D descendant state with a set of low-energy modes whose number grows with the number of legs and whose momenta are inherited from the 2D surfaces.
• These multi-mode quasi-1D liquids constitute a new and previously unanticipated class of quantum states interesting in their own right.