Electronic and structural properties of alkali doped SWNT

Comprehensive experiments on structural and transport properties of alkali intercalated single walled carbon nanotubes (SWNT) are presented. The increasing electron density was measured as a shift of the Drude‐edge in optical reflectivity in‐situ with progressive doping. In saturation‐doped samples the Drude‐edge shifts into the visible (to 25,000 – 30,000 cm−1 for potassium and rubidium doped samples) and the samples have a golden‐brown color, similar to stage I graphite. X‐ray diffraction reveals a crystalline rope structure with expanded lattice constant, similar to results of Duclaux et al.. The change in the low temperature divergence of the resistivity after degassing at high temperature and high vacuum and after K‐doping is studied in‐situ.