Dynamical properties of bidirectional charge-density-waves in ErTe$_3$

TL;DR

This paper investigates the distinct sliding behaviors of bidirectional charge density waves in ErTe$_3$, revealing that the lower temperature CDW exhibits significantly less mobility due to stronger pinning effects, impacting their collective dynamics.

Contribution

It provides the first detailed comparison of the dynamical properties of bidirectional CDWs in ErTe$_3$, highlighting the influence of pinning on their sliding behavior.

Findings

The upper CDW slides more freely than the lower one.

The lower CDW shows a tenfold reduction in excess current.

Stronger pinning likely inhibits the lower CDW's motion.

Abstract

We report a strong difference in the sliding properties of the bidirectional charge density wave (CDW) in the two-dimensional rare earth tritelluride ErTe$_3$ which occurs below $T_{CDW1}=265$ K with a wave vector along $c$-axis and below $T_{CDW2}=165$ K with a wave vector along $a$-axis; the excess current carried by the motion of the CDW is 10 times less for the lower CDW compared with the value of the upper one. We tentatively explain this result by a stronger pinning of the lower temperature CDW intricated with the upper one, which inhibits its motion and may generate a phase slippage lattice.