Three-dimensional Fermi-surface of CeTe₂ studied by angle-resolved photoemission

Angle-resolved photoemission spectroscopy on a quasi-two-dimensional strongly correlated Ce 4f electron compound CeTe₂ has been performed to elucidate the importance of the three-dimensionality at the electronic structure in understanding its anomalous physical properties such as a complicated charge density wave formation. We have found that the Fermi surface as well as the band structure show the characteristic three-dimensionalities as follows: (1) a systematic reduction of the spectral weight at the hole-like Fermi surface along the Γ M line away from the ZR line suggests the imperfect nesting along the [1 1 0] axis; (2) the anomalous dispersive feature which is suggestive of the "band-folding" along the Γ Z line. The observed three-dimensionality indicates the existence of the three-dimensional nesting vector on CeTe₂.