Strong charge density wave fluctuation and sliding state in PdTeI with quasi-1D PdTe chains

TL;DR

This study reveals strong charge density wave fluctuations, a pseudogap state, and a sliding CDW in PdTeI with quasi-1D chains, showing unique magnetoresistance behavior and field-induced localization.

Contribution

It uncovers the coexistence of strong CDW fluctuations, a pseudogap, and sliding CDW in PdTeI, highlighting its potential for studying CDW phenomena and magnetic interactions.

Findings

Carrier concentration decreases before CDW transition at ~110 K

Sliding CDW state appears below ~6 K

Exotic magnetoresistance behavior observed

Abstract

In quasi-one-dimensional (quasi-1D) system, the charge density wave (CDW) transition temperature TCDW is usually lower than the mean-field-theory predicted TMF and a CDW fluctuation region exists between them. Here, we investigate the physical properties of PdTeI single crystal containing quasi-1D PdTe chains. Surprisingly, we find that the carrier concentration decreases gradually before the long-range CDW ordering state occurring at T1 ~ 110 K, reflecting the existence of strong CDW fluctuation with possible pseudogap state at T >> T1 because of dynamic charge separation of Pd ions (Pd3+ -> Pd2+ + Pd4+). Moreover, the sliding CDW state appears below T2 ~ 6 K. Combined such low T2 with the feature of multiple quasi-1D bands, PdTeI exhibits exotic crossover behavior from negative to huge positive magnetoresistance under magnetic field and field-induced localization. Thus, PdTeI provides a novel platform for studying the CDW fluctuation and the interplay between magnetic field and CDW state.