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Charge-density-wave instabilities driven by multiple umklapp scattering

Peter Schmitteckert·Ralph Werner
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Abstract

We show that the concept of umklapp-scattering driven instabilities in one-dimensional systems can be generalized to arbitrary multiple umklapp-scattering processes at commensurate fillings given that the system has sufficiently longer range interactions. To this end we study the fundamental model system, namely interacting spinless fermions on a one-dimensional lattice, via a density matrix renormalization group approach. The instabilities are investigated via a new method allowing to calculate the ground-state charge stiffness numerically exactly. The method can be used to determine other ground state susceptibilities in general.

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Peter Schmitteckert, Ralph Werner. 2003-11-12. Charge-density-wave instabilities driven by multiple umklapp scattering. https://doi.org/10.1103/physrevb.69.195115

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