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arXiv · 1610.05024

Dimensional Crossover in a Charge Density Wave Material Probed by Angle-Resolved Photoemission Spectroscopy

Christopher W. Nicholson·Christophe Berthod·Michele Puppin·Helmuth Berger·Martin Wolf·Moritz Hoesch·Claude Monney
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Abstract

High-resolution angle-resolved photoemission spectroscopy (ARPES) data reveal evidence of a crossover from one-dimensional (1D) to three-dimensional (3D) behavior in the prototypical charge density wave (CDW) material NbSe3. In the low-temperature 3D regime, gaps in the electronic structure are observed due to two incommensurate CDWs, in agreement with x-ray diffraction and electronic-structure calculations. At higher temperatures we observe a spectral weight depletion that approaches the power-law behavior expected in 1D. From the warping of the quasi-1D Fermi surface at low temperatures, we extract the energy scale of the dimensional crossover. This is corroborated by a detailed analysis of the density of states, which reveals a change in dimensional behavior dependent on binding energy. Our results offer an important insight into the dimensionality of excitations in quasi-1D materials.

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Christopher W. Nicholson, Christophe Berthod, Michele Puppin, Helmuth Berger, Martin Wolf, Moritz Hoesch, Claude Monney. 2017-05-22. Dimensional Crossover in a Charge Density Wave Material Probed by Angle-Resolved Photoemission Spectroscopy. https://doi.org/10.1103/physrevlett.118.206401

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