Impact of disorder in the charge-density-wave state of Pd-intercalated ErTe${}_3$ revealed by the electrodynamic response

Abstract

It is a general notion that disorder, introduced by either chemical substitution or intercalation as well as by electron-irradiation, is detrimental to the realisation of long-range charge-density-wave (CDW) order. We study the disorder-induced suppression of the in-plane CDW orders in the two-dimensional Pd-intercalated ErTe${}_3$ compositions, by exploring the real part of the optical conductivity with light polarised along the in-plane $a$ and $c$ axes. Our findings reveal an anisotropic charge dynamics with respect to both incommensurate unidirectional CDW phases of ErTe${}_3$, occurring within the $ac$-plane. The anisotropic optical response gets substantially washed out with Pd-intercalation, hand-in-hand with the suppression of both CDW orders. The spectral weight analysis though advances the scenario, for which the CDW phases evolve from a (partially) depleted Fermi surface already above their critical onset temperatures. We therefore argue that the long-range CDW orders of ErTe${}_3$ tend to be progressively dwarfed by Pd-intercalation, which favours the presence of short-range CDW segments for both crystallographic directions persisting in a broad temperature ($T$) interval up to the normal state, and being suggestive of precursor effects of the CDW orders as well as possibly coexisting with superconductivity at low $T$.

16 pages, 17 figures

References in corpus (10)

• Theory of Intertwined Orders in High Temperature Superconductors
• Nematic and meta-nematic transitions in the iron pnictides
• Semimetal to semimetal charge density wave transition in 1T-TiSe${}_2$
• Alternative route to charge density wave formation in multiband systems
• Emergence of Fermi pockets in an excitonic CDW melted novel superconductor
• Observation of a Charge Density Wave Incommensuration Near the Superconducting Dome in CuxTiSe2
• Coexistence and competition of multiple charge-density-wave orders in rare-earth tri-telluride RTe3
• Magnetic properties of the charge density wave compounds RTe3, R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er & Tm
• Suppression of charge density wave order by disorder in Pd-intercalated ErTe${}_3$
• Robust superconductivity intertwined with charge density wave and disorder in Pd-intercalated ErTe${}_3$

Cited by in corpus (1)

• Evolution of charge-density-wave soft phonon modes in ${\mathrm{Pd}}_x{\mathrm{ErTe}}_3$