Avoiding Stripe Order: Emergence of the Supercooled Electron Liquid

TL;DR

This paper investigates how electrons can form a supercooled, glassy liquid state that avoids charge order, using theoretical models that align with experimental observations in organic compounds.

Contribution

It provides a theoretical framework using Extended Dynamical Mean Field Theory to explain supercooled electron liquids and their glassy behavior in the absence of disorder.

Findings

Identification of a pseudogap phase at intermediate temperatures

Metastability of the liquid phase below the stripe transition temperature

Resistivity increase and density of states suppression indicating kinetic arrest

Abstract

In the absence of disorder, electrons can display glassy behavior through supercooling the liquid state, avoiding the solidification into a charge ordered state. Such supercooled electron liquids are experimentally found in organic $\theta$-$MM'$ compounds. We present theoretical results that qualitatively capture the experimental findings. At intermediate temperatures, the conducting state crosses over into a weakly insulating pseudogap phase. The stripe order phase transition is first order, so that the liquid phase is metastable below $T_s$. In the supercooled liquid phase the resistivity increases further and the density of states at the Fermi level is suppressed, indicating kinetic arrest and the formation of a glassy state. Our results are obtained using classical Extended Dynamical Mean Field Theory.