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Infrared signature of the charge-density-wave gap in $ZrTe_3$

A. Perucchi·L. Degiorgi·H. Berger
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Abstract

The chain-like $ZrTe_3$ compound undergoes a charge-density-wave (CDW) transition at $T_{CDW}=63$ $K$, most strongly affecting the conductivity perpendicular to the chains. We measure the temperature ($T$) dependence of the optical reflectivity from the far infrared up to the ultraviolet with polarized light. The CDW gap $Δ(T)$ along the direction perpendicular to the chains is compatible for $T<T_{CDW}$ with the behavior of an order parameter within the mean-field Bardeen-Cooper-Schrieffer (BCS) theory. $Δ(T)$ also persists well above $T_{CDW}$, which emphasizes the role played by fluctuation effects.

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A. Perucchi, L. Degiorgi, H. Berger. 2005-03-15. Infrared signature of the charge-density-wave gap in $ZrTe_3$. https://doi.org/10.1140/epjb%2Fe2006-00006-4

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