Breakup of the Fermi surface near the Mott transition in low-dimensional systems

TL;DR

This paper explores the Mott transition in coupled 1D fermionic chains, revealing an intermediate phase with Fermi surface pockets and anisotropic quasiparticle spectral weight, which could appear as arcs in experiments.

Contribution

It introduces a generalized DMFT approach to study the Mott transition in low-dimensional systems, identifying a novel intermediate phase with Fermi surface pockets.

Findings

Mott gap is suppressed at a critical interchain hopping.

An intermediate phase with electron and hole pockets emerges.

Quasiparticle spectral weight is highly anisotropic.

Abstract

We investigate the Mott transition in weakly-coupled one-dimensional (1d) fermionic chains. Using a generalization of Dynamic Mean Field Theory, we show that the Mott gap is suppressed at some critical hopping $t_{\perp}^{c2}$. The transition from the 1d insulator to a 2d metal proceeds through an intermediate phase where the Fermi surface is broken into electron and hole pockets. The quasiparticle spectral weight is strongly anisotropic along the Fermi surface, both in the intermediate and metallic phases. We argue that such pockets would look like `arcs' in photoemission experiments.