Disorder Quenching of the Charge Density Wave in ZrTe3

Abstract

The charge density wave (CDW) in ZrTe3 is quenched in samples with small amount of Te isoelectronically substituted by Se. Using angle-resolved photoemission spectroscopy we observe subtle changes in the electronic band dispersions and Fermi surfaces on Se substitution. The scattering rates are substantially increased, in particular for the large three-dimensional Fermi surface sheet. The quasi-one-dimensional band is unaffected by the substitution and still shows a gap at low temperature, which starts to open from room temperature. The detailed temperature dependence reveals that the long-range order is absent in the electronic states as in the periodic lattice distortion. The competition between superconductivity and CDW is thus linked to the suppression of long-range order of the CDW. arXiv:1712.03379v1 [cond-mat.supr-con]

Role of a higher-dimensional interaction in stabilizing charge density waves in quasi-one-dimensional NbSe3 revealed by angle-resolved photoemission spectroscopy

“…In particular, there is the possibility that the electronic gaps survive well above the transition temperature while the CDW loses long-range phase coherence. This has previously been observed in various CDW materials [37][38][39] as well as in superconductors [40].…”

Distinction between pristine and disorder-perturbed charge density waves in ZrTe3

“…A pronounced resistivity anomaly can be observed at 63 ± 1 K ( Supplementary Fig. 1), a temperature that is usually referred to as the CDW ordering temperature, T CDW , in earlier literature [34][35][36][37][38][39] . The Fermi surface, contributed by four bands, comprises two sectors ( Fig.…”

“…1c), where strong electron-phonon coupling puts high weights in this region in the k-average for the purpose of CDW formation 34 . Indeed, the CDW electronic gap is most prominent in this region 36,39 . As these electronic states are removed from the Fermi surface by the gap, however, the remaining states available for nesting may require a slightly different q avg than q CDW , making the FO and the CDW wave vectors depart (depicted by cyan and orange arrows in Fig.…”

“…1a), with wave vector q CDW ¼ ð0:07a à ; 0; 0:33c à Þ. The electronic gap associated with the CDW order opens near the D-point of the BZ 36,39 , where electron-phonon coupling is strongest 34 .…”

“…In contrast, in both this scenario and our original interpretation based on FOs, the sharp peak at T LO < T < T CDW arises from CDWs that are indirectly induced and pinned at distance from the disorder, since it dominates the signal and produces the static speckles, and because it continuously evolves below T LO into the peak of truly long-range CDWs. Regarding the detuning in q between the two peaks, although the presence of impurity in ZrTe 3 may locally modify the electronic structure 39 or create topological defects in the CDWs, it remains to be investigated why the detuning effect gradually develops below T CDW and is not present at T CDW .…”