Fermi gas behavior of a one-dimensional metallic band of Pt-induced nanowires on Ge(001)

We have investigated the electronic band structure of Pt-induced nanowires on Ge(001) [Pt/Ge(001) NWs] by angle-resolved photoelectron spectroscopy at 6 K. Single-domain samples of Pt/Ge(001) NWs were prepared on vicinal Ge(001) substrates. One of the bands disperses only in the nanowire direction, and its Fermi surface consists of strictly straight lines, indicating that it is an ideal one-dimensional metallic state. An energy distribution curve of the one-dimensional band is explained by a Fermi-Dirac-type spectral shape, which is against both a Luttinger liquid and Peierls instability schemes.