Strong coupling expansion of the t-V model (further results)

We employ a strong coupling expansion - similar to the one used in the lattice field theory studies [1] - to solve the one-dimensional extended t-V model of fermions on a lattice [2]. This model is solved for a range of filling factors, including both commensurate - where a charge density wave is present - and incommensurate densities. The first set consists not only of a trivial case of half filling. The method allows us to trace the transition from a Luttinger liquid phase to a Mott insulating phase and calculate the critical parameter K. This simple yet powerful method is not based on Bethe ansatz and it works for both integrable and non-integrable systems. Furthermore, we investigate how tailoring the interaction can introduce other ordered phases of the system [3].References:[1] C.J. Hamer, Phys. Lett. B 82, 75-78 (1979); D.P. Crewther, C.J. Hamer, Nucl. Phys. B 170, 353-368 (1980).[2] G. Gómez-Santos, Phys. Rev. Lett. 70, 3780 (1993); R.G. Dias, Phys. Rev. B 62, 7791 (2000).[3] P. Schmitteckert, R. Werner, Phys. Rev. B 69, 195115 (2004); T. Mishra et al., Phys. Rev. B 84, 115135 (2011).