▎ 摘　　要

The presence of strong disorder in graphene nanoribbons yields low-mobility diffusive transport at high charge densities, whereas a transport gap occurs at low densities. Here, we investigate the longitudinal and transverse magnetoresistance of a narrow (similar to 60 nm) nanoribbon in a six-terminal Hall bar geometry. At B = 11 T, quantum Hall plateaus appear at sigma(xy) = +/- 2e(2)/h, +/- 6e(2)/h, and +/- 10e(2)/h, for which the Landau-level spacing is larger than the Landau-level broadening. Interestingly, the transport gap does not disappear in the quantum Hall regime, when the zero-energy Landau level is present at the charge neutrality point, implying that it cannot originate from a lateral confinement gap. At high charge densities, the longitudinal and Hall resistance exhibit reproducible fluctuations, which are most pronounced at the transition regions between Hall plateaus. Bias-dependent measurements strongly indicate that these fluctuations can be attributed to phase-coherent scattering in the disordered ribbon.