Possible Evidence for Superlocalization on Fractal Network from the Thermopower Data

The theory for the thermoelectric power in the variable-range hopping is extended to the fractal regime where the wavefunctions of the electronic states are superlocalized. The thermopower is shown to scale as T^{D/(D+ )}, where D is the fractal dimension and  the superlocalization exponent. Recent thermopower data on doped polyacetylene samples are examined and it is found that their temperature dependence agrees with the present theory. The superlocalization exponent obtained is consistent with existing theory and numerical results. We demonstrate that the data can be regarded as evidence for the superlocalization on fractal network.