Dimensional tuning of electronic states under strong and frustrated interactions

Phys Rev Lett. 2008 May 9;100(18):186404. doi: 10.1103/PhysRevLett.100.186404. Epub 2008 May 8.

Abstract

We study a model of strongly interacting spinless fermions on an anisotropic triangular lattice. At half-filling and the limit of strong repulsive nearest-neighbor interactions, the fermions align in stripes and form an insulating state. When a particle is doped, it either follows a one-dimensional free motion along the stripes or fractionalizes perpendicular to the stripes. The two propagations yield a dimensional tuning of the electronic state. We study the stability of this phase and derive an effective model to describe the low-energy excitations. Spectral functions are presented which can be used to experimentally detect signatures of the charge excitations.