Spin Bose-Metal phase in a spin-1/2 model with ring exchange on ladders

I will discuss recent developments in the study of a 2D quantum phase of strongly correlated spins, the Spin Bose-Metal (SBM), a spin liquid characterized by gapless excitations residing on surfaces in momentum space (i.e. ``Bose surfaces''). Thus far, significant progress has been made by considering a triangular lattice Heisenberg model with a four-site ring exchange term on a 2-leg strip (see [1]), where quasi-1D signatures of the parent 2D phase can be detected (i.e. ``Bose points''). The ladder systems have provided a fruitful scaffolding for the implementation of the quasi-exact numerical method DMRG, as well as a theoretical approach via slave particles and Bosonization. To test the theory numerically, variational Monte Carlo (VMC) is employed with Gutzwiller projected products of Slater determinants as a direct comparison with DMRG results. Here, I will present new results for 3- and 4-leg ladders as we continue to drive towards two dimensions where this phase is potentially relevant in the study of organic Mott insulators near the metal-insulator transition. Indeed, we will offer evidence that the phase diagram of the 4-leg triangular ladder contains a Spin Bose-Metal phase. [1] D. N. Sheng \emph{et al}., Phys. Rev. B {\bf 79}, 205112 (2009).