Anomalous Anderson Weak Localization of Graphite Thin Film Fabricated by Plasma-Enhanced Chemical Vapor Deposition

The conductivity and magnetoresistance of graphite thin film (GTF), fabricated by plasma-enhanced chemical vapor deposition (PECVD), were investigated. Below 100 K, the conductivity was proportional to log T , and the transverse magnetoresistance (MR) was negative, whereas the longitudinal MR was small, but positive. The conductivity and magnetoresistance results are well-described by weak-localization theory, applied to a two-dimensional disordered system. The carrier dephasing length ( L ε ), which was estimated from the transverse MR, varied as T - p ( p = 0.05–0.11). This p value is an order of magnitude smaller than that of electron–electron interaction derived from Fermi liquid theory ( p = 1). This small p value strongly suggests that the electronic state of GTF is different from that of typical graphite.