Defect-induced shift of the Peierls transition in TTF-TCNQ thin films

TL;DR

This study examines how substrate material and film thickness affect the Peierls transition temperature in TTF-TCNQ thin films, revealing that defects caused during growth lower the transition temperature compared to single crystals.

Contribution

It demonstrates the impact of substrate and growth conditions on the Peierls transition in TTF-TCNQ thin films and links defects to the lowered transition temperature.

Findings

Peierls transition temperature is lower in thin films than in single crystals.

Substrate material and growth conditions significantly influence film morphology.

Defects during growth are responsible for the shift in transition temperature.

Abstract

In this paper we investigate the influence of the substrate material and film thickness on the Peierls transition temperature in tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) thin films, grown by physical vapor deposition. Our analysis shows that the substrate material and the growth conditions strongly influence the film morphology. In particular, we demonstrate that the Peierls transition temperature in thin films is lower than in TTF-TCNQ single crystals. We argue that this effect arises due to defects, which emerge in TTF-TCNQ thin films during the growth process.