Commensurability Transition and Stripe Phases in the Ginzburg-Landau Theory

TL;DR

This paper models the thermodynamics of charge and spin density waves in doped high-temperature oxides, identifying stable stripe phases and a commensurability transition, with implications for understanding phase transitions in these materials.

Contribution

It provides a phenomenological Ginzburg-Landau framework describing stripe phases and the commensurability transition in high-$T_c$ oxides, including explicit solutions and symmetry analysis.

Findings

Identification of stable non-homogeneous stripe solutions.

Discovery of a commensurability transition separating incommensurable phases.

Stripe criticality compatible with second order phase transition.

Abstract

We phenomenologically describe the thermodynamics of charge and spin density waves in doped high-$T_{c}$ oxides. We have explicitly calculated stable non-homogeneous solutions in the incompressible spin driven stripe phase, where stripes are static soliton-like charge density waves (CDW), and in the vicinity of their critical point, where CDW's become harmonic. Our phase diagram points to a commensurability transition separating the low (LI) and high (HI) incommensurable phases. Besides, we demonstrate by rigorous group symmetry arguments that the stripe criticality is compatible with a second order phase transition.