Quantum Paramagnet in a π Flux Triangular Lattice Hubbard Model

We propose the pi flux triangular lattice Hubbard model (pi THM) as a prototypical setup to stabilize magnetically disordered quantum states of matter in the presence of charge fluctuations. The quantum paramagnetic domain of the pi THM that we identify for intermediate Hubbard U is framed by a Dirac semimetal for weak coupling and by 120 degrees Neel order for strong coupling. Generalizing the Klein duality from spin Hamiltonians to tight-binding models, the pi THM maps to a Hubbard model which corresponds to the (J(H); J(K)) = (-1, 2) Heisenberg-Kitaev model in its strong coupling limit. The p THM provides a promising microscopic testing ground for exotic finite-U spin liquid ground states amenable to numerical investigation.