The Mixed State of Charge-Density-Wave in a Ring-Shaped Single Crystals

TL;DR

This paper investigates how the curvature of ring-shaped crystals causes geometrical frustration in charge-density-wave (CDW) phases, leading to a mixed state similar to that in type-II superconductors, using a mean-field Ginzburg-Landau approach.

Contribution

It introduces a theoretical model showing that ring-shaped CDW crystals experience frustration and form a mixed state, expanding understanding of phase behavior in geometrically constrained systems.

Findings

CDW in ring-shaped crystals undergoes frustration due to curvature.

The mixed state in ring-CDW is analogous to type-II superconductor behavior.

Phase transition characteristics are discussed in relation to recent experiments.

Abstract

Charge-density-wave (CDW) phase transition in a ring-shaped crystals, recently synthesized by Tanda et al. [Nature, 417, 397 (2002)], is studied based on a mean-field-approximation of Ginzburg-Landau free energy. It is shown that in a ring-shaped crystals CDW undergoes frustration due to the curvature (bending) of the ring (geometrical frustration) and, thus, forms a mixed state analogous to what a type-II superconductor forms under a magnetic field. We discuss the nature of the phase transition in the ring-CDW in relation to recent experiments.