Fermi Surface Reconstruction in the CDW State ofCeTe3Observed by Photoemission

${\mathrm{C}\mathrm{e}\mathrm{T}\mathrm{e}}_3$ is a layered compound where an incommensurate charge density wave (CDW) opens a large gap ($\simeq 400\mathrm{m}\mathrm{e}\mathrm{V}$) in optimally nested regions of the Fermi surface (FS), whereas other sections with poorer nesting remain ungapped. Through angle-resolved photoemission, we identify bands backfolded according to the CDW periodicity. They define FS pockets formed by the intersection of the original FS and its CDW replica. Such pockets illustrate very directly the role of nesting in the CDW formation but they could not be detected so far in a CDW system. We address the reasons for the weak intensity of the folded bands, by comparing different foldings coexisting in ${\mathrm{C}\mathrm{e}\mathrm{T}\mathrm{e}}_3$.