Magnetic spin susceptibility and optical conductivity from 1 to 100 meV and at 9 GHz are presented for the recently discovered alkali-metal fulleride linear polymers, (AC60)n (A=K, Rb, and Cs). We find that (KC60)n is a metal with an enhanced Pauli susceptibility and a low-frequency conductivity decreasing with increasing temperature. (RbC60)n and (CsC60)n are also conducting at high temperatures but have a metal-insulator transition at 50 and 40 K, respectively. The data are suggestive of a quasi-one-dimensional instability towards a condensed spin-density-wave state.
ASJC Scopus subject areas
- Condensed Matter Physics