The electrical transport properties of the iodine-doped ultrathin polyacetylene of 100nm thickness were studied as a function of temperature (I.3K∼300K) and magnetic field (up to 6.5 Tesla). The temperature dependence of resistivity shows the 3-dimensional variable-range-hopping behavior for the highly resistive sample, power-law dependence for the intermediately resistive one, and the logarithmic dependence for highly conducting film. Magnetoresistance is positive for all samples below T≈4K, and its magnitude decreases as the sample becomes more conducting. The anisotropic magnetoresistance is observed for the highly conducting sample. The obtained results are discussed in terms of the spin-dependent varible-range-hopping conduction and the possible characteristics of the ultrathin polyacetylene film.
- Polyacetylene and derivatives
- Transport measurements