Dynamical transport properties of NbSe$_3$ with simultaneous sliding of both charge density waves

TL;DR

This study investigates the nonlinear conductivity of NbSe3 with simultaneous sliding of both charge density waves, revealing strong interactions and distinct Shapiro step behaviors under RF fields.

Contribution

It provides new insights into the interaction effects between high-T and low-T charge density waves in NbSe3 during sliding.

Findings

Threshold electric field for high-T CDW increases 4-5 times with low-T CDW formation.

Shapiro steps are not observed simultaneously for both CDWs under RF fields.

Different RF field regimes show selective Shapiro step observation for each CDW.

Abstract

Measurements of the nonlinear conductivity in NbSe$_3$ when the high-T and the low-T charge-density waves (CDWs) are simultaneously sliding have been performed. It is shown that the threshold electric field, $E_{t1}$, for depinning the high-T CDW increases 4 - 5 times at the temperature at which the low-T CDW is formed, indicating the strong pinning effect resulting from the interaction between both CDWs. Under application of a radio-frequency (rf) field, Shapiro steps are never observed simultaneously for both CDWs. At the electric field less then one for high-T CDW sliding only Sapiro steps for low-T CDW were observed, and at higher field only Shapiro steps for high-T CDW exist.