Spectroscopic signatures of the Mott transition on the anisotropic triangular lattice

Abstract

We use a new Monte Carlo method to study the Mott transition on the anisotropic-triangular-lattice Hubbard model. Our real space approach accurately treats the emergence of non-trivial magnetic correlation in this frustrated structure with reducing temperature. For hopping anisotropy typical of the two-dimensional organic salts, the coupling of electrons to self-generated magnetic moments leads to a pseudogap, huge d.c. resistivity, and non-Drude optical response over a wide temperature window. In addition to these generic signatures of a "bad metal", the spatial correlation among the magnetic moments leads to pronounced momentum dependence of quasiparticle extinction and pseudogap formation on the Fermi surface as the Mott transition is approached.