Angle-resolved photoemission study of the evolution of band structure and charge density wave properties in RTe_ {3}(R= Y, La, Ce, Sm, Gd, Tb, and Dy)

Physical review. B, Condensed matter (Impact Factor: 3.66). 06/2008; 77(23). DOI: 10.1103/PhysRevB.77.235104
Source: arXiv


We present a detailed angle-resolved photoemission spectroscopy (ARPES) investigation of the RTe3 family, which sets this system as an ideal “textbook” example for the formation of a nesting driven charge density wave (CDW). This family indeed exhibits the full range of phenomena that can be associated to CDW instabilities, from the opening of large gaps on the best nested parts of Fermi surface (up to 0.4 eV), to the existence of residual metallic pockets. ARPES is the best suited technique to characterize these features, thanks to its unique ability to resolve the electronic structure in k space. An additional advantage of RTe3 is that the band structure can be very accurately described by a simple two dimensional tight-binding (TB) model, which allows one to understand and easily reproduce many characteristics of the CDW. In this paper, we first establish the main features of the electronic structure by comparing our ARPES measurements with the linear muffin-tin orbital band calculations. We use this to define the validity and limits of the TB model. We then present a complete description of the CDW properties and of their strong evolution as a function of R. Using simple models, we are able to reproduce perfectly the evolution of gaps in k space, the evolution of the CDW wave vector with R, and the shape of the residual metallic pockets. Finally, we give an estimation of the CDW interaction parameters and find that the change in the electronic density of states n(EF), due to lattice expansion when different R ions are inserted, has the correct order of magnitude to explain the evolution of the CDW properties.

Download full-text


Available from: Zahid Hussain, Oct 05, 2015
21 Reads
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The antiferromagnetic transition is investigated in the rare-earth (R) tritelluride RTe3 family of charge density wave (CDW) compounds via specific heat, magnetization and resistivity measurements. Observation of the opening of a superzone gap in the resistivity of DyTe3 indicates that additional nesting of the reconstructed Fermi surface in the CDW state plays an important role in determining the magnetic structure. Comment: 4 pages, 5 figures
    Physical review. B, Condensed matter 05/2008; 78(1). DOI:10.1103/PhysRevB.78.012410 · 3.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: de Haas-van Alphen oscillations were measured in lanthanum tritelluride (LaTe(3)) to probe the partially gapped Fermi surface (FS) resulting from charge density wave (CDW) formation. Three distinct frequencies were observed, one of which can be correlated with a FS sheet that is unaltered by CDW formation. The other two frequencies arise from FS sheets that have been reconstructed in the CDW state. All three pockets are quasi-two-dimensional, consistent with expectations from band-structure calculations. Analysis of the field dependence of the oscillations is used to provide an estimate of the geometry of the reconstructed FS sections.
    Physical review. B, Condensed matter 05/2008; 78(4). DOI:10.1103/PhysRevB.78.045123 · 3.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Obtaining insight into microscopic cooperative effects is a fascinating topic in condensed matter research because, through self-coordination and collectivity, they can lead to instabilities with macroscopic impacts like phase transitions. We used femtosecond time- and angle-resolved photoelectron spectroscopy (trARPES) to optically pump and probe TbTe3, an excellent model system with which to study these effects. We drove a transient charge density wave melting, excited collective vibrations in TbTe3, and observed them through their time-, frequency-, and momentum-dependent influence on the electronic structure. We were able to identify the role of the observed collective vibration in the transition and to document the transition in real time. The information that we demonstrate as being accessible with trARPES will greatly enhance the understanding of all materials exhibiting collective phenomena.
    Science 09/2008; 321(5896):1649-52. DOI:10.1126/science.1160778 · 33.61 Impact Factor
Show more