Slowing down of the relaxational dynamics at the ferroelectric phase transition in one-dimensional (TMTTF)2AsF6

TL;DR

This study investigates the dielectric response of (TMTTF)2AsF6 near its ferroelectric transition at 100 K, revealing a critical slowing down of relaxational dynamics consistent with a classic ferroelectric transition.

Contribution

It provides detailed dielectric measurements over a wide temperature and frequency range, characterizing the relaxational dynamics near the ferroelectric transition in a quasi-one-dimensional material.

Findings

Continuous slowing down of relaxation time near Tc

Critical rise of dielectric constant at transition

Evidence supporting a classic ferroelectric transition scenario

Abstract

We present measurements of the dielectric response of quasi one-dimensional (TMTTF)2AsF6 in a wide temperature and frequency range. We provide a thorough characterization of the relaxational dynamics observed close to the ferroelectric-like transition at Tc = 100 K. Our measurements, extending up to 100 MHz, reveal a continuous slowing down of the mean relaxation time when approaching Tc from high as well as from low temperatures. The simultaneous critical rise of dielectric constant and relaxation time point to an explanation of the transition in terms of a classic ferroelectric scenario.